<%BANNER%>

Transmission properties of sub-wavelength hole arrays in metal films

University of Florida Institutional Repository
xml version 1.0 encoding UTF-8
REPORT xmlns http:www.fcla.edudlsmddaitss xmlns:xsi http:www.w3.org2001XMLSchema-instance xsi:schemaLocation http:www.fcla.edudlsmddaitssdaitssReport.xsd
INGEST IEID E20101118_AAAACW INGEST_TIME 2010-11-18T21:53:25Z PACKAGE UFE0015340_00001
AGREEMENT_INFO ACCOUNT UF PROJECT UFDC
FILES
FILE SIZE 22678 DFID F20101118_AABVPG ORIGIN DEPOSITOR PATH woo_k_Page_109.jpg GLOBAL false PRESERVATION BIT MESSAGE_DIGEST ALGORITHM MD5
cadd213e6dad79c4a7f41381433bf2b6
SHA-1
59b60f03ef83326c7c2165ed6f0e0d58e12b8ca9
8510 F20101118_AABWID woo_k_Page_153.pro
3caf1c6231b50203ac39a1a826866e1f
1454f8eb68ef9bc0434291b4e9b5cce7d98152a0
67766 F20101118_AABVOS woo_k_Page_094.jpg
3ccbf8435ac835b12f01ce6c195b82bc
657ef76859eebfde76d881880877d1d10223f9b4
9234 F20101118_AABWHP woo_k_Page_139.pro
47e028b75dbac83603ebb4815e9b3a8e
a10bfbba04133fdb214d1b27b0947e595169a4de
21735 F20101118_AABVPH woo_k_Page_110.jpg
a17d3a7f573d45ac8169fd2db2bef778
c6d1bb2bbe75848ed3720e5e02bf92e5262ac5c6
8110 F20101118_AABWIE woo_k_Page_154.pro
aaf0421e1d0b0d8a0b74faccbf18c641
652f847b72a4834220af38bcd7de3b1dbba932b0
62011 F20101118_AABVOT woo_k_Page_095.jpg
4648736b992f8325ca41b14185d90441
d5778cbfe8d7e63aad1fd259865bdd7e02e4e324
34257 F20101118_AABWHQ woo_k_Page_140.pro
90a66e0d2fcd8e41c869fed1963c1430
0b399da33818e99de719410bd31706f7f32e3413
24643 F20101118_AABVPI woo_k_Page_111.jpg
91cf1cf77ca9846cf2fa9f4edab1e7b4
9473d2738162eeef9c37dc87545661b6f0545797
36595 F20101118_AABWIF woo_k_Page_155.pro
569839b4e734cbe8397544326607ece8
aa2a117a62f17bf734b685733af68f57dc4a8e90
73929 F20101118_AABVOU woo_k_Page_096.jpg
4a54b0800010bd0af1f1ffc560cc3327
a2196eb317d1828a5fd1f81081e5ffd70428c875
43434 F20101118_AABWHR woo_k_Page_141.pro
6774e0b8171bafb2d8609aa2892d9207
4d49981eee33f8bbb1362f8279fddb2d784878b6
19693 F20101118_AABVPJ woo_k_Page_112.jpg
ff191f2433ae0ea9333efc73f19a9b4e
aa7b590cdae434ff29b9aa4fe0c35a12a76d4ffc
46247 F20101118_AABWIG woo_k_Page_156.pro
bb3cfa7bf47d5b28511296e1a0a11804
d2d7d2358584567fb95b9bf3f55a7a35d843c9e2
69083 F20101118_AABVOV woo_k_Page_097.jpg
35ea9ad7993b50c374fde5208efa7c52
56f6cbc0f6be6c68711abb0dc9ccfe577b29fa9a
20642 F20101118_AABWHS woo_k_Page_142.pro
b637df4889ad4dd71895016432f1ba45
1fc13c95f00877f65c9f763144861c0aa573d7b5
19750 F20101118_AABVPK woo_k_Page_113.jpg
edebd2963c326dede572e57dc39ac529
6d8700d1ce3921daa24fbe71175bc94ea093eda8
48418 F20101118_AABWIH woo_k_Page_157.pro
28df4a9f5fe189de8a91e9ae5076322e
efe21030a6ba207a218c042fe7b13ec5f84ce8c4
73559 F20101118_AABVOW woo_k_Page_098.jpg
524de369f6aa00dedd2613c7299b88f6
95cb4766636cece82cd4f9d6e2917f21dfd5a484
2182 F20101118_AABWHT woo_k_Page_143.pro
0ab88a602098ed4d249e3998b4ad1a5f
6504a2d8af1cf3e513bd60653381db4f7e377763
20283 F20101118_AABVPL woo_k_Page_114.jpg
ed3d3d3e32eb84de4f47a5f2e1d91c3d
f97e5dd0bb979d39d2b1967d978623621dcabe78
20135 F20101118_AABWII woo_k_Page_158.pro
ef0df1fcec91b62400cb4e42437ab263
c3e6f000eaac688dfebc1f2fbcce72f8ec3b3536
70361 F20101118_AABVOX woo_k_Page_099.jpg
67a666c373fb0dbfe55214032b691db0
d7d9895cc5a95d8b3219ec5f917e141f4fb83bf8
21821 F20101118_AABWHU woo_k_Page_144.pro
c6faa95ff8bee6bdd99bb7ffa34b854d
57bcf8193f044cc9f6cfebc25c22c1f1a876df63
20092 F20101118_AABVQA woo_k_Page_129.jpg
39f3525b28316a7c280a6387e51df4e7
c7e3fe9461365076f1c8279e8215737540c6b8ca
19386 F20101118_AABVPM woo_k_Page_115.jpg
a267f37b94e0eb94ca17aad6d00c6c07
f6490d0935651a00ec8161247f0864a452926603
21885 F20101118_AABWIJ woo_k_Page_159.pro
671d796c87ed94f65d23057a576e4341
46b7c54948c71ef5e015a227e7816b2bf6bddbc2
67862 F20101118_AABVOY woo_k_Page_100.jpg
909c9cb12325cf0286e27389802a5ba1
b6deda3d0556d2855b1d6560d6fd53801fdc0576
44016 F20101118_AABWHV woo_k_Page_145.pro
8e634d1cda0316f3296a6f5a0bf98bc6
01c8b9c4f4f029591d2ac1a93e5d22006e20b713
69992 F20101118_AABVQB woo_k_Page_130.jpg
92d3962ec45cff218008582e9d48aa3b
14b71d7c844ca4cd6a54294f6a2e1f33d14acea9
20266 F20101118_AABVPN woo_k_Page_116.jpg
8bfefe14249f037110fc1fa28ab81d2c
3403f3b65fa98b69f36d32fff6825e6e9284fda0
453 F20101118_AABWIK woo_k_Page_001.txt
318acfd32a2b894fcd506372211b7fea
dc76b2deecf6d5467c7fc419aad43f1933d6c481
26491 F20101118_AABVOZ woo_k_Page_101.jpg
1d1111d543a3752018ec667616ba1511
6fc81a4a6a644871886bf7b3f3713eb99f4f5995
6034 F20101118_AABWHW woo_k_Page_146.pro
006d0cedbf35fe5bee01a033ddad71d6
52d83c0355cd308dbb51ca9944829e5c9e862839
19988 F20101118_AABVQC woo_k_Page_131.jpg
7846d974e31919aa809c6590d1ad8cad
a2a5da94a85b51c37443fcc8ef7d2c755d3adf68
24759 F20101118_AABVPO woo_k_Page_117.jpg
7f8ea28b9b5860eaf9db7c8a73a3b42f
f877cbb7a66e8797deab0a82df4af84ab06b4184
106 F20101118_AABWIL woo_k_Page_002.txt
fef3b7cbc7d89ef78f5f4e30e56369dd
1127d6d15f840a2b25032c67fe77db05bf471078
36381 F20101118_AABWHX woo_k_Page_147.pro
8fd041102e79c974d5ffd3bdb47eda8a
2ef4ad290bc30e061676e19fb7532cdf509d1892
22484 F20101118_AABVQD woo_k_Page_133.jpg
4aca8d5a943a38bb9b37878ac5c5c2e9
9bcee346c5248c4135a321f1505992e8502040e7
1781 F20101118_AABWJA woo_k_Page_017.txt
da35a097793432898eb63262c44928be
e4dc65209fa5ae2057dccfe975369bb6d2c505fa
24803 F20101118_AABVPP woo_k_Page_118.jpg
bb4048c93bbf6328926f225e1d1ffd1e
15369bdbde25ec1f972e8001c4dff4fb7c4754e7
1327 F20101118_AABWIM woo_k_Page_003.txt
3c4e6132bfb14e891134d63a97a74e4c
6e1ec835adeb66e64fc4758250ee6c13bef7be50
6155 F20101118_AABWHY woo_k_Page_148.pro
df2c1e2879c1df2184592faff05c82da
43f7db16b35bdbbb7450ad306fca7e76af2ff261
74741 F20101118_AABVQE woo_k_Page_134.jpg
b3046c6c40136021f7e8a8913e1741a9
954799a2d5f7a85776842d86bd326ef65581df81
1646 F20101118_AABWJB woo_k_Page_019.txt
1ccb28b75dee0ed459aaa122a59f231d
c5f6033c6b2658a71071fb256f3b53efc5edcbe8
24379 F20101118_AABVPQ woo_k_Page_119.jpg
010fb3f80f3afaef3a3713802dde18da
4262d74e2214b3e51fe23df7eb1d6e4312a62d6f
3024 F20101118_AABWIN woo_k_Page_004.txt
086a0ab424d488ceff80c364bf852146
246e506adf3806f02fb54fd659b6e56d2f7db032
1677 F20101118_AABWHZ woo_k_Page_149.pro
487646892b5d257651c948bee47bf69c
d80e2c06ad0603aeb60f58e1e756cdd1bff48acf
25367 F20101118_AABVQF woo_k_Page_135.jpg
add5ceca11f6de5217e8fa1e8b36931a
684bca0272b7da99f8e59d88b4a9561d24f65832
1810 F20101118_AABWJC woo_k_Page_021.txt
fbc448606ba6055bf5ba42495d16a503
48b822ea90e5329437418b3e5e8439f6f00abef7
24965 F20101118_AABVPR woo_k_Page_120.jpg
dafae15b7450d00d022c7cf58f819c42
56a8d85f78b25efca964143e8c4f948f60202b28
3918 F20101118_AABWIO woo_k_Page_005.txt
f56a7468b5c771da04386868e694ecba
e1ecbc8d9b120bf64dae78c1d8b99c44803c45bb
79723 F20101118_AABVQG woo_k_Page_136.jpg
1b443ac2b46006110e3b17ea5d25f6e1
6946ad0cd1871c76173ecd098bdb70894a85f6c8
1526 F20101118_AABWJD woo_k_Page_022.txt
c2e6846ddec705baf4f63517264fb275
188bd1479447311a63c40dad20f8d3b65a686b3f
66362 F20101118_AABVPS woo_k_Page_121.jpg
afa6c9dd6365e3db4f8b173ae5162131
6f8404f526b1419c43bd959a99186087519be2bb
514 F20101118_AABWIP woo_k_Page_006.txt
6547da8fa012fd5a41ab696fdf123f87
b5cfef1145595027bc1b1ad0b2534f7b49f8a3c6
1458 F20101118_AABWJE woo_k_Page_023.txt
c56f43a5c362b940edf149047ca9a6d4
049b4765c4685190314015dd2bef91a9b0ec22ec
34767 F20101118_AABVPT woo_k_Page_122.jpg
12c611099cdd5458da91d8ab3eb7e36f
1cf931659f83ad2399ed4e56bd3bdfe6a6d97bd5
804 F20101118_AABWIQ woo_k_Page_007.txt
ea896f7d5ef06be09a5b62092828878d
d7df6cf007000532292bec66de9c8cc4e1582a86
79487 F20101118_AABVQH woo_k_Page_137.jpg
d6ac7ee05a43e4a971a1de0d95e82c4b
4a016fae4d58dba7156ac6e052fc7a542c7e9fd7
1668 F20101118_AABWJF woo_k_Page_024.txt
f8b66e29219c7d30dc1b54ce7da609c1
24a2a5770f32884a75a8597c77c11067118c1cf1
21318 F20101118_AABVPU woo_k_Page_123.jpg
5953e72080ce8baa050f428943fa38e1
68701f66ad82de4c7a80375952c56cf48a90acf9
2597 F20101118_AABWIR woo_k_Page_008.txt
fb8a71a8ecc9247fbfb2393d7ad5683b
23b119e924285821da9f80bc15d3604144a188bb
80286 F20101118_AABVQI woo_k_Page_138.jpg
a709acaa8455268f494a41626b6ebef0
23cbb4a3e8e042b63b610a2fd3d1ffbfc07fa60f
1044 F20101118_AABWJG woo_k_Page_025.txt
a0ccdd0c920be84a34a3b25b786dfd37
9aabbf847df70f09189bb878fd8953de39ae7214
69743 F20101118_AABVPV woo_k_Page_124.jpg
4ca7a3a6f8c5339afb6b7a42dcef12e5
5c9cf8f82e808a68257248b2d65455e1dc3bac1b
2976 F20101118_AABWIS woo_k_Page_009.txt
76718d53f3ec3dfe0f8885e7f6f65eca
fb3035f61a3fdce5c4216137504554f47997243b
24014 F20101118_AABVQJ woo_k_Page_139.jpg
95e9be1ea2cbf772c4fd2ed3a7afc94c
d4f93dad41aa7368a15b02ce849ea4191c970044
1333 F20101118_AABWJH woo_k_Page_026.txt
407ea4bd89230fd1913536c0beb7ba55
6e0e1a52769928c60b405fbba06ed6903f9088d8
20137 F20101118_AABVPW woo_k_Page_125.jpg
ac9e79103e23f7d575c8baa3e0184e91
cd5201e511a9e37e8a968e6c49671574f642744e
3114 F20101118_AABWIT woo_k_Page_010.txt
027e9410b5109d185a8280c2d51cc62e
41a87d63ddaeba026f4d0d1a7fdf73f4bfede86c
80258 F20101118_AABVQK woo_k_Page_141.jpg
74d5ea2cb2975ac970a98cb19d92d56d
f8afa913e37e29628e74d3c3840319985551d74e
1750 F20101118_AABWJI woo_k_Page_027.txt
fc79d26a95044db9883e16da5fbf3207
80900da2bf2c01293edd1ce7efb021611eafad33
70156 F20101118_AABVPX woo_k_Page_126.jpg
f9b7793316655b3d10a831120f6dc10a
cc6b4731d9fdb58381ff1351235de8689f45753c
354 F20101118_AABWIU woo_k_Page_011.txt
d2a759061f595566142931293c323009
d6c45f33e35cdd6ae9e655fbfa388ccda6c7827d
70386 F20101118_AABVRA woo_k_Page_157.jpg
59a916115d0d916cc1833c7ce7fefe72
b926e70d5e7c618f4cded83045bc33bc32d547ca
43184 F20101118_AABVQL woo_k_Page_142.jpg
7142f96ada2684c6c712e08b5e2622ad
0d9a4cf5c4bea8a1815d5e773f3679f812587498
1212 F20101118_AABWJJ woo_k_Page_028.txt
38aa9c74f03166cdd31e3b9d7c691632
7f7bd93ff5471d5e2d5597fbf478712c4f7b5ac8
20074 F20101118_AABVPY woo_k_Page_127.jpg
04a7d9129f33aac64cf0091d1817eede
69dcb54eb66c8701e23242714d0e5509ff28e003
1737 F20101118_AABWIV woo_k_Page_012.txt
b12a816bd2dc3e18125ec6c05c8399da
0d11f5a1fcb099af5d080960a62106556550d423
34808 F20101118_AABVRB woo_k_Page_158.jpg
109571e5f393208354d6c23457617904
ed7283ca80ec8ab2a7d1b81f63251ce4e3e03fe5
23878 F20101118_AABVQM woo_k_Page_143.jpg
5aea454e51821e41705e834e99d280da
f61d20193d37b5b4704cbd190d1f44e5180376fd
1820 F20101118_AABWJK woo_k_Page_029.txt
8c93fd0ba96c077729b87f74a45a2784
44a1b0ce387ddf793c78976e635be67f577fe9e1
75561 F20101118_AABVPZ woo_k_Page_128.jpg
d6966749c304e952b0e3b5b313f2b0f4
23f26da72cf024cfbef28a59d81975b60447e508
669 F20101118_AABWIW woo_k_Page_013.txt
ba97fcbbe25f1255b480b09d52ba39a2
982b3996319de0fb15dc00f8d5151af9115e710c
37117 F20101118_AABVRC woo_k_Page_159.jpg
6ce06cf3cfd7ee2d7cffd2908e303fdd
463d810d31bcfc35fe8ae5f19033d1ec0024b8be
81173 F20101118_AABVQN woo_k_Page_144.jpg
9fce6fb7877b989a0e8482cf4529dfb1
1d4af673c0c13668279f2778aea43b87b1239fe7
1914 F20101118_AABWJL woo_k_Page_030.txt
a5aeb5353d79ca23303c2304e8df5d25
98bdae5d39bdee8535efe21ea460bd52272f7553
1873 F20101118_AABWIX woo_k_Page_014.txt
60c7c9c9ca462fadd5ee67159335cb6b
c8e4a3c7102cd73a5b16ad9a3d5f8a76b3ced6a5
23156 F20101118_AABVRD woo_k_Page_001.jp2
4c21651dc424786518e67b60874c1e7a
1a1cef8f07ee0908273d73e12712cd48a12494be
79939 F20101118_AABVQO woo_k_Page_145.jpg
4310c1903a7223a4d04ff182432df18d
a028261a9ad63b6a0437afcc70e36aacceffbdc1
634 F20101118_AABWJM woo_k_Page_031.txt
cb3186f7ed993ec90f5c92220f7736b6
9928481bf68ef7358167c8ed8821d1a0b0f5b50b
1956 F20101118_AABWIY woo_k_Page_015.txt
f74821f6dec036b04a3eda2c226cbc91
96a395c61c59977cf7c51b7e3f7ea3d7839d95d4
5578 F20101118_AABVRE woo_k_Page_002.jp2
714e04ca4618f8f9b68243e8338ec8d7
6b015963ac3c6b09dd6627c0f7dfac32255e98b2
1443 F20101118_AABWKA woo_k_Page_047.txt
630588067b832b8107b4a70d390e429e
63536ea0cbea91ee488b1ab87252356aa745c2c6
22088 F20101118_AABVQP woo_k_Page_146.jpg
f990b95cbc4b279a862898eeebe49291
220f6fe70f57cafb6d784810f0fca1182879c0cb
1829 F20101118_AABWJN woo_k_Page_032.txt
6a016f19f590b91f8e40d4540e23ea18
cf0c4b48180bafdbc475d2442f15de3b032646f9
923 F20101118_AABWIZ woo_k_Page_016.txt
4c2f0bcc37e3d5815cd5930dd5f5b045
9daa1a58c6d391bf87f1523dc02ddaedeba02a4e
1051945 F20101118_AABVRF woo_k_Page_004.jp2
9e5ab47a09dd4012108f74fcbaff1218
c3d54513fe345ec79a34234d4429686edb36cf87
1707 F20101118_AABWKB woo_k_Page_048.txt
c9c784744e8fbd648b3d23163c22bdeb
02914ea06da75918c6f6bb2588bb5b09694e438f
75518 F20101118_AABVQQ woo_k_Page_147.jpg
48abfe5b61d6d5d40bb631dbcde94758
5b08943faaf85769e8715503d99898ec61f40f93
1647 F20101118_AABWJO woo_k_Page_033.txt
39e53e9169d57420d4ce91a4b70518ea
e2853cad13ea8ee0674e5afae02217187b1cdbd9
415294 F20101118_AABVRG woo_k_Page_006.jp2
d3a83af5e13c16d7f3892726e4a84dd2
9cfbfb437de9277139b02f148f9c011c0880dc56
1238 F20101118_AABWKC woo_k_Page_049.txt
b7ad72453e59d9aafb4cb1010dacdba7
14c7add88176bdfc6cc50225f862e91a187d95ee
21519 F20101118_AABVQR woo_k_Page_148.jpg
e1351d4e363ce9e21fb3fe1bea99ec16
26f5d0af4a7063ae0179ecd6401bd8a9ddff8dba
1280 F20101118_AABWJP woo_k_Page_034.txt
6fbbb8d567daddc5936b742027d5c976
8854915e56d796aea5dc8cd611740cb1568b56c3
690904 F20101118_AABVRH woo_k_Page_007.jp2
bd0a6eb81724c972f7ccc5823c2e82ef
093640a18fdf27dd6cb28e7c86bca49d44b01244
1528 F20101118_AABWKD woo_k_Page_050.txt
84331406238a42accf6c94bdcd8798bd
e08615c611c444832b4314478b23d409974e0409
36619 F20101118_AABVQS woo_k_Page_149.jpg
e1855722a2e7eee2b9f8f6e61778ae0a
59e94f4c869e06c76805fe951556b5898c4abd71
1428 F20101118_AABWJQ woo_k_Page_035.txt
460901cf036d0aab16dfa893f1fcc039
f127cede531e2adeeae0cc9a34591eb97e8330e9
1603 F20101118_AABWKE woo_k_Page_051.txt
e6c40cbbab480d890b5d2adac0ee26b4
09456102240904f95fd11deb84471f2c5a9c4dfa
23081 F20101118_AABVQT woo_k_Page_150.jpg
87a7b390e309222633ea0c0c099c6948
786518a8e20f575bb75699e5cbc9668025b2a552
2002 F20101118_AABWJR woo_k_Page_036.txt
f134263b8e3a0b4f7c40e64c67810e2c
11da59292338f8b99a6072e98b2cf92f81da549e
1051967 F20101118_AABVRI woo_k_Page_008.jp2
1c00c9fde72d5c0ee6a038bf638d6ccd
4bc0ac61cd6712d689475f71586317c5c005b4df
1806 F20101118_AABWKF woo_k_Page_052.txt
50532008abe390c0e0796df051f618ad
373219f1d4f540fd694791e71c84ffa1c832c16f
23129 F20101118_AABVQU woo_k_Page_151.jpg
f831e9de8018210995661a8a2b7aee48
5a8686f5237b365f31628de24f132c93cce07ef1
2103 F20101118_AABWJS woo_k_Page_038.txt
82294e39b4685fb7f0579ba1e8a320c8
0a4cd776e7fd7899a69f93f874f0a9f8a9b8cf1e
1051979 F20101118_AABVRJ woo_k_Page_009.jp2
877a867844c9ba4671374bdcf1ab3b8c
002f61e1315469945fb67302f24e4427a97b1fa6
569 F20101118_AABWKG woo_k_Page_053.txt
18031d4a123d16e779fa04d1a34d039c
98302900c1286dd060616add9e275751be47b05e
23506 F20101118_AABVQV woo_k_Page_152.jpg
ad385b86efebdb143e568bf3188b0d07
dcbd4a5906c236fe8c40cc7e1426eb65483753a3
2035 F20101118_AABWJT woo_k_Page_039.txt
9af00e244406c066916a69dfca19cc2c
e777ace7129871aca57f4caa185a40118b329ae0
1051981 F20101118_AABVRK woo_k_Page_010.jp2
d214ddc0bc993d9e7a4fb833a4ead1e6
58ef960dc96e34b75c183bd2ec03d0955102cb5f
1709 F20101118_AABWKH woo_k_Page_054.txt
0ecf4da0f32705ebf965102136dc0345
9d53e00bf3fcd3ef9d01226f41af3c62a0064725
24162 F20101118_AABVQW woo_k_Page_153.jpg
b8ded6b43e4b56c810b01cd386c3ffc3
37ce71c8da165250abda988fecebead24aa61dfe
780 F20101118_AABWJU woo_k_Page_040.txt
7d257dc1449400c43421ca9a0c6f7086
bda5f6e09cbac8e610d8af650e116782e6f60437
80442 F20101118_AABVSA woo_k_Page_027.jp2
cc711a853bc76ef177edacc40ef50cb8
32564d250d0faa20093ffd39587e09dd0ff0a237
332841 F20101118_AABVRL woo_k_Page_011.jp2
74fdc1ff74a211d7359c09dd98d0e2dc
23717d3fb04421c6c68ca2c7e6753869f82c94b7
1009 F20101118_AABWKI woo_k_Page_055.txt
3868ba5f92e96c01c6f06984f80027c9
4af045d1fc8b4f8a4f2e027129c95992b32289cf
26485 F20101118_AABVQX woo_k_Page_154.jpg
31a7fd607a611190177edf31ab578da0
e84ba84d323bd845b0fabc480a5e77a462db1170
293 F20101118_AABWJV woo_k_Page_041.txt
5a6d78727c3b8b6da4b61d88e15219ce
2201bef280960f9304a157a86557d8e3ab9ac967
718665 F20101118_AABVSB woo_k_Page_028.jp2
6110fcd6fe56122528136a33fd43e243
c4eeb23060db5762231c68e9280797138a98db12
86889 F20101118_AABVRM woo_k_Page_012.jp2
3be12b323d42ba71f2f892fd4f5fa1e1
7921f0ae8dc6c3e32db04c1c11a05875b996dec1
2286 F20101118_AABWKJ woo_k_Page_056.txt
67a7d55003f36ea56902eeb4e35f1dee
876f04f58d3140e2e3c851f27c4dcd3fca1a5875
55901 F20101118_AABVQY woo_k_Page_155.jpg
349575f36e97fcb015cab29bf71850c8
e01578f6c09854357ed91c5e0e2d9eb01a47252d
1779 F20101118_AABWJW woo_k_Page_042.txt
eaf7798bf3ea6088aa7b14f808cdce7e
b9e01b32e2217a305115962ea2a0914084f91ff7
90804 F20101118_AABVSC woo_k_Page_029.jp2
545941bd73207388cebeb9bec44dbf7d
7f0cd8ca414a203ce88a15f90b20f482376bc797
40084 F20101118_AABVRN woo_k_Page_013.jp2
f794d52311498c76e41c323d93050e33
cb0c68e8cc53eee53f338d72523715e071d8c7c6
1453 F20101118_AABWKK woo_k_Page_057.txt
a4a77cb18fa6d760a8a2f0ba4019ff4d
87a8d41938a8d89269c5d78f78d2a0a50cd5fb98
67151 F20101118_AABVQZ woo_k_Page_156.jpg
b86d4607e52fae4e6104b883b4a77f44
c5c10616130a7e0595570817b803fcfa962ce075
102054 F20101118_AABVSD woo_k_Page_030.jp2
900571db5830516bd99f748d1226d2e5
c1259021f89cdf0125dfd440848f477ddf576ebe
1004 F20101118_AABWLA woo_k_Page_073.txt
b1b3fa85b9cdf5880438fbdee1af3fe8
3090004791d9bbb3e1854e46a98e5ba76623de64
96894 F20101118_AABVRO woo_k_Page_014.jp2
38feab71c72d23b41353f1ac6f72406d
3fa2cf1cb37fc393e7b7063aa253bebc2ef711fa
684 F20101118_AABWKL woo_k_Page_058.txt
56cf58e168b45b82ae68f353b6f7a466
7fece925f203a36fa8891194f65fc0b84b37d30c
450 F20101118_AABWJX woo_k_Page_043.txt
a04c79e6f17413705a58fa068f94f190
3e5b4987544628d4f284e9f2403fbf9e6a116d04
841970 F20101118_AABVSE woo_k_Page_031.jp2
0a9905eada59060c60c12909b9767d35
daf35fb5ebfa702dc6624abe4aad15c853c6ce51
104448 F20101118_AABVRP woo_k_Page_015.jp2
b7370007cf80572178bf7ef5301b4b70
21947361e6db6216f0af5bece5d7554588a538c3
1859 F20101118_AABWKM woo_k_Page_059.txt
e6d84672520a6b14622b447b46dc92c4
2cd0ce5a3e854b6540b3c8baeb2bdd56a9c27b8b
1579 F20101118_AABWJY woo_k_Page_044.txt
c693834b35bc365813ca91299d3caef8
44ca94340e10c2d6e28f1956db09ef66fd3f4047
93133 F20101118_AABVSF woo_k_Page_032.jp2
4241ba74b06df08060c8e7f34e842bcd
735e251c2d5bc2308cbe3339e2140d6247bc96a8
1475 F20101118_AABWLB woo_k_Page_074.txt
9865ca60c85cb2e2491179f57023441d
6f4987f20455fe8ab7a873ebd8e3f2896fe36b3e
94855 F20101118_AABVRQ woo_k_Page_017.jp2
da089ca57ec7dccdc08a94d298f49b50
98dbec276e82bef8c08d5240cfc6f5fb68269cbb
1056 F20101118_AABWKN woo_k_Page_060.txt
a5fb9110a20c1d66c31214a586a39ed8
1ce12a25544a352ca53a29bad10f0cc9bdff63fe
1481 F20101118_AABWJZ woo_k_Page_046.txt
1fb9e403c769b0edc60c8672f966659d
ef2b2814f48915ec214ab7d3e0dd7afd27c93e65
79684 F20101118_AABVSG woo_k_Page_033.jp2
7852179e05970afef8734a7df95cc301
4e816bf7518ed2791a9dcd184acc1faa937c8060
1171 F20101118_AABWLC woo_k_Page_075.txt
4380b244d022ff701e0103ee8566de88
3cc16e164e8f330056be977f8e503a45d301fa5b
105021 F20101118_AABVRR woo_k_Page_018.jp2
a4237d89c100e7f3e23432df872539bc
c9bbfa7c60ffd5d750ade65f568dfd4aba3397f8
1354 F20101118_AABWKO woo_k_Page_061.txt
f683b93cf50d6279f42e18f49493f7aa
ccba7d4602be2d41bdc3b55b4a7f360debbcedb3
663195 F20101118_AABVSH woo_k_Page_034.jp2
0d42827b96ba122cdc6934b42569cd4c
c0d7c62faa7787fb10183c7cf0e179dd6c1f801c
1908 F20101118_AABWLD woo_k_Page_076.txt
57eaf7ef61cfdc10d8d07249cfc1ead9
97daf7c83839acc0496519e45ffee254e10c8942
75745 F20101118_AABVRS woo_k_Page_019.jp2
a17ec147f68bfdc737bb2d83812b0f18
f32a034f083bd1fb71b012ba6b1bca1a06d046fd
1052 F20101118_AABWKP woo_k_Page_062.txt
6fa9901dc252555c907f4974fce952fa
3735615ac517dfa671c3c69d3c0a2e6377e6af57
680028 F20101118_AABVSI woo_k_Page_035.jp2
395779e046cdfbcfce222cf695cc277f
d67c37f8f62f28ddb1634513538a584350169c1c
1948 F20101118_AABWLE woo_k_Page_077.txt
089475506c5bd230c0ca93bc3e31f3b4
db8556f980fa65855006182d1394281bcc5f94dd
99210 F20101118_AABVRT woo_k_Page_020.jp2
a1680ca1f890d25f1260402db4674275
fd798d1af91236966aaadc7953888e78e295f940
1970 F20101118_AABWKQ woo_k_Page_063.txt
98c660b56f9ec389bda54cb1798f295d
535cccf984237739b9a05cf006a5d4aaa7400eee
718 F20101118_AABWLF woo_k_Page_078.txt
2138b79afaa870116e4eaac62b37c6a3
5658785e89e862293fa9c8f2e80d51c163cbd55f
77936 F20101118_AABVRU woo_k_Page_021.jp2
53df013cdcf220ea021a36cabc7b706b
fb62d092bac9bb0de582291ae0284be96a4432ec
1301 F20101118_AABWKR woo_k_Page_064.txt
acc9cebc46680689d9b283a4b3fc8cb7
58681f66c678458799224ecbb6405723cfeda707
108243 F20101118_AABVSJ woo_k_Page_036.jp2
6f6d2ae4d8695a3f8c1de92d1154ba0a
64521691bd2faea3840d8ea19453af021084f750
908 F20101118_AABWLG woo_k_Page_079.txt
d8a78425b03385dd86c0b90c594636e9
c193b60b7e2e8ca93a02752cc0cfad6a7afc8182
55116 F20101118_AABVRV woo_k_Page_022.jp2
c9c02966c7c37455c19462bddc0bc8f3
e45efcf50091fd6be5ebdb290e7801c0ef7bae56
1985 F20101118_AABWKS woo_k_Page_065.txt
e62f0d01b61a03dda01c62548fc1e7c9
184efd097088343c00400bd21454629da5be6608
1051972 F20101118_AABVSK woo_k_Page_037.jp2
5467d0b9b43f4c355c043769edb60593
a474614474d0b4c7ca342ca63999687396fc4987
557 F20101118_AABWLH woo_k_Page_080.txt
10e2c72a206efe81bc662255d9690339
de06d0b230de7fce1d14c4bf4bed4d3ede61bf7b
54476 F20101118_AABVRW woo_k_Page_023.jp2
7b28c54e51622f551c01a5ed74fc7389
40296cd482f696b91bbef6e41ec2afe0d452012a
496 F20101118_AABWKT woo_k_Page_066.txt
12c58628414dc1c4d4477fe7419cdaf7
ab4ee9c8b8ec1455b57cd6a2c79454eab5a33725
111111 F20101118_AABVSL woo_k_Page_038.jp2
1ca25f6cd1adba585b1a365096222673
e472fa8450760cca0102fc692d1a4bf0facec864
1719 F20101118_AABWLI woo_k_Page_081.txt
25d024506a7a84ac582ede62073f0013
23094cb6ea931c92227d52c745812c49036089bf
59266 F20101118_AABVRX woo_k_Page_024.jp2
fdc378ce119b7644904cc20dd847f2e4
efee2477666831939c2102cb75a341ddb2df6f43
1609 F20101118_AABWKU woo_k_Page_067.txt
a3f8937f9939896975883b60f1689638
72194056badb046d911d631e104e24eaa2a53dd8
87946 F20101118_AABVTA woo_k_Page_054.jp2
37555dd00531ee91a4e31cecdc4c1847
cea944ea86244f33848149e2d0eb1a999c82ca52
110892 F20101118_AABVSM woo_k_Page_039.jp2
6861b5c85e235c86855263def3e3caeb
aab483eebee157a0f733621a3705bcf0850e95c7
1963 F20101118_AABWLJ woo_k_Page_082.txt
107ae8df23f9e262ff3eb7d7751f773c
17de902cccd1d008fb4ade471316a9268910a0b4
480803 F20101118_AABVRY woo_k_Page_025.jp2
090be90034c1752eb74a8b9f67256397
13daea65b28f1711d7813cc1cca28d544ed4a783
1994 F20101118_AABWKV woo_k_Page_068.txt
e9d927ae5970d9fd17f14d77030c0e26
113c35140ef5754f91748a7391bf77699534f259
1051978 F20101118_AABVTB woo_k_Page_055.jp2
88f5f13bf181ce8d646101c7395ac2b0
a26917c3bc9f81ae1746049fd6be60266ec3f130
495205 F20101118_AABVSN woo_k_Page_040.jp2
477766e9738d51c3d8679d525749678f
5367529f42d9fd39c8a1ba26a9ec9df2d9148755
1596 F20101118_AABWLK woo_k_Page_083.txt
40193b7d43d517c23b8236b92fa1ce57
2160569195deffb8b9a68a0deeef592a2f9f0bf2
700496 F20101118_AABVRZ woo_k_Page_026.jp2
ddf3f221dca3375e1e0fc1e2b2623f46
8526ff6d81dd7174f212a5271018a27bb6063edd
1051 F20101118_AABWKW woo_k_Page_069.txt
5389d3fc07d160d521f97ed213b52052
3478fa06ecbd90e8b57a8f41d830fe1e99a8a5d1
101766 F20101118_AABVTC woo_k_Page_056.jp2
d7d0a09e2ad2cbe39e1e4cb010abebc8
c066aeecfe77c9186eb0d59fddbeba52f0d703cc
234594 F20101118_AABVSO woo_k_Page_041.jp2
f961e7e6efca9ec9ceb0c080b507d48f
b78688f86d0a26f6c9a6aa52136ba7a898169ad6
1884 F20101118_AABWLL woo_k_Page_084.txt
d1cef6a50ce773296ddfb802081d9b15
93f7d35a56206a08a6fbd032b7b832d75e56317a
910 F20101118_AABWKX woo_k_Page_070.txt
8d4c15948fec76bc230cbd6ff5894676
7ba0ecdbc39aac90fab7d212d538b953f14798ef
96628 F20101118_AABVTD woo_k_Page_059.jp2
f641e4cc9f00e1c6e8ec65823b236a1a
3cc6399713dec4e2c18ea32cff7b94e53673dd8c
577 F20101118_AABWMA woo_k_Page_102.txt
1ca0e29c479ab583628305e393a356e9
87c83b27833201f475b3b831500caa4a870ead39
93445 F20101118_AABVSP woo_k_Page_042.jp2
2688189b43412f9c5e9cd06a63e84fd0
777c1d3ae16a7fbb03205ce5a5dd0aaa92c70d8d
1976 F20101118_AABWLM woo_k_Page_085.txt
cb6aeabfb0aa8c0e2ef314bb7e078e74
320501bee5c067c9f57309fac7cc258a7d6e66fe
1845 F20101118_AABWKY woo_k_Page_071.txt
641f7eb5345e853ddf44cc3671292a66
7898b44008decee882b996e29ab0d3e6cd5aad1d
728717 F20101118_AABVTE woo_k_Page_060.jp2
0c790a98451c2e2b52dddbf2ae35abac
dad73cd80def1522c80328525d17f9533aefed15
489 F20101118_AABWMB woo_k_Page_103.txt
7df32b2b084bb94a438892d928664d84
4853b6e638fee3e0f92de01ab7ba488b28e03fe1
868515 F20101118_AABVSQ woo_k_Page_044.jp2
105e973adfb2ce35e8f6473653ad118e
096ca7501c5fe96b69f8af427000c27afc41e49a
1664 F20101118_AABWLN woo_k_Page_086.txt
06958a8e13fa771fdfbee184f19b6c6b
09080c1fefba22201250dfdc79332413858b0765
1058 F20101118_AABWKZ woo_k_Page_072.txt
3756b864e934cb613b7fc42d6ce888ae
d47037510729d9157307c75bf972b66477609cd9
852907 F20101118_AABVTF woo_k_Page_061.jp2
42cfb2ab1254036ba4b8239cba15e48e
7d6539ff28c8570b0ca8593b3304a4d05ef83c1f
84253 F20101118_AABVSR woo_k_Page_045.jp2
41d33899aafc45432973549f16b6d319
25583e850d07d8f4cd83b961554e96f1793f10fd
1748 F20101118_AABWLO woo_k_Page_087.txt
3b3f02b08ee11cb935f1d2db15046513
b0f4de902a90605649c4cd45b13bbf25d70ac456
894590 F20101118_AABVTG woo_k_Page_062.jp2
ccd85672114a2b4aba7bcf974882c73f
a01e42e37378410562f15e0484d88af1eae73387
1784 F20101118_AABWMC woo_k_Page_104.txt
c421ee394338153c46d2cea483987776
c04cfe152b02ed57b4666122b748eadb3213afbc
709724 F20101118_AABVSS woo_k_Page_046.jp2
e9ed05d53d2b87860455668094e2954b
983c09cb4babc5c02cce903944168c387269cc10
894 F20101118_AABWLP woo_k_Page_089.txt
7bd1083bf0f565273079313917e6bdf5
185a3b003a3b0cf85617c6409c7303929272478d
105968 F20101118_AABVTH woo_k_Page_063.jp2
812316f562e64d10fdc33ed3a23cf047
550319ab1dbef6138f2c0561df464502691112cd
2013 F20101118_AABWMD woo_k_Page_105.txt
e9b35142cba56ae07fcd8aae4e948608
137c139aef6f8149a6cf1e981df79f5ebc1e560d
735140 F20101118_AABVST woo_k_Page_047.jp2
28808dede598158ece3b976ccced0a96
374c30ad2ca8cb358c6295614bc96e469dc576be
851 F20101118_AABWLQ woo_k_Page_090.txt
10931e44e9c6bf9af60423e0e9ac184a
a5b2cbc7ad10f0165248f25c123700121ea1b9ea
106302 F20101118_AABVTI woo_k_Page_065.jp2
7997987499b1269cb6bff3e9ad335f1f
4168aa768e4ad4d2e7567a92d426fbed190c81d0
F20101118_AABWME woo_k_Page_106.txt
ef3b663581ff55fd4df70ae60a2e7cf0
11d2b2639ce17f874a0e48024e3a8ace8edb1808
87715 F20101118_AABVSU woo_k_Page_048.jp2
85150af817970bea1713abfa5dad305c
eae39944ee5e69949f4a7ab525a41f8fbc940c29
898 F20101118_AABWLR woo_k_Page_091.txt
6f55f2e9aded45b148e53c862868453b
af78d2ba5a7ab42a0033e59c9cb8711b82d28525
699823 F20101118_AABVTJ woo_k_Page_066.jp2
df677d9f46a89b938604350d2545ad64
9882a39aff3ba5c9f62fa0c093171825820ced2d
379 F20101118_AABWMF woo_k_Page_107.txt
1b85e7ef7b013f0a445970440b70e35c
30990893666778aa91186eb2592fdd9e37fc02aa
419917 F20101118_AABVSV woo_k_Page_049.jp2
be6c68351cb54412075f5b9c3c610a98
b0f74bf849fa4f43935a9c34073350e034406f44
1174 F20101118_AABWLS woo_k_Page_092.txt
a55d1b28727af06544a278bf415ec664
0a316af02da891e90c196b960e8fa7294f447441
452 F20101118_AABWMG woo_k_Page_108.txt
18e09a08585231039ad6dcbe5e094900
632ce1cac31629c749df745dc2e482d2bb0689d6
67037 F20101118_AABVSW woo_k_Page_050.jp2
f9c2da438df2e6d42f3e34617043845e
c1f6c3c9bbb088c1c25bb8059e7a3412c10c39d8
727 F20101118_AABWLT woo_k_Page_093.txt
52c0c312fd1212bd5cd4cbd1ec2c8ff8
078881b9ded3f8754e6484f75eb2b30e835dd638
892208 F20101118_AABVTK woo_k_Page_067.jp2
56be4a55406e0a33e37f23345c6ad04d
69282f6c5813159c136679b8622a3440281c703d
F20101118_AABWMH woo_k_Page_109.txt
eb85831a6310a02c958ea366dea616bc
c91ba2b5033775347d8246671dc32db23d1b019b
68910 F20101118_AABVSX woo_k_Page_051.jp2
d90ee8b3a99a030fd542e462a060e472
50d0fabae914ef43aeb01a714be013616468c34c
1818 F20101118_AABWLU woo_k_Page_095.txt
ab3623cab6015a0cee4d90b374c9634e
aeb90aba26bc52177b4231872630f0b7c5f0e339
836236 F20101118_AABVUA woo_k_Page_083.jp2
52294473410dab69896c0178634f6033
08ec46bd81bc6f4930a69f1efca146760c6c6550
106888 F20101118_AABVTL woo_k_Page_068.jp2
f952b5d3d89f803f228778d10888e783
b0270fc395cf64b4d841a5e24b099362e5467fe6
360 F20101118_AABWMI woo_k_Page_110.txt
0e21cb0665de94a79c2aa279fa5353f1
b6b04c8d32beecb92557af8b336ea125560f5696
2066 F20101118_AABWLV woo_k_Page_096.txt
e2148c9eb1cc315465ba82f4df02e4bf
04555ca6e1465a2b6ee1482b8e079226a5f7d2a2
96736 F20101118_AABVUB woo_k_Page_084.jp2
4ef5f359abcdca3a4a328dc97c313142
4dbaba44f7505174fa08f5709729deca65546cf7
824375 F20101118_AABVTM woo_k_Page_069.jp2
f9e53f09fa4d0fb5fa70f0a9cfa4ab12
b23c5ae84bb0ef53b5e7c27965aaba11d364502f
204 F20101118_AABWMJ woo_k_Page_111.txt
b53b40a1a3534b50a734a3f4bd04a855
031beec2473e90668f71c4d2d1718d376775d278
1051957 F20101118_AABVSY woo_k_Page_052.jp2
3d9c308f0f145b6d7ed3433f7d1fcecf
092e0d2aa183eb796710bfe2e8dfc558d45276d6
1951 F20101118_AABWLW woo_k_Page_097.txt
015bc8260cc372fe49a231ea68a947d1
ce18243121455d37e91493994360680afb29e31d
811299 F20101118_AABVUC woo_k_Page_087.jp2
835cd223767601f37546cbf17b7b9302
afd6cdb0fb238dd62aaa9d36b7c60ebbc65d42bc
895751 F20101118_AABVTN woo_k_Page_070.jp2
f634fe597644cb86ad3f6fcfb7cee2b7
7cf9e4535c5db7a92cf091aea578748b62c47241
424 F20101118_AABWMK woo_k_Page_112.txt
b14edae53fc96779d415f07a57817caf
735a3ff48f78f577f5020887c7732ec178e4f871
30833 F20101118_AABVSZ woo_k_Page_053.jp2
6f274745eef297d4726b4e9edddd89c9
8c2353207a275ef0bdb9cef3f6b4ce01e2d9e7f8
F20101118_AABWLX woo_k_Page_099.txt
6d17ea25043a9b9ff9ed3fcb3a8a913e
ce1038378c111d781630306784736cb84fb091af
681588 F20101118_AABVUD woo_k_Page_088.jp2
e42867be1a21e4987ce4962c769bc31d
72408b09e79b240e6a0e60d044b20c4818ba2f3b
169 F20101118_AABWNA woo_k_Page_129.txt
39d7a0fb485d5ae5a53a97327c4cd337
5e6d520533da17203e9aadc7fa90d80da987bda4
99245 F20101118_AABVTO woo_k_Page_071.jp2
5f7e541f017e78b6786b307e3ea0eb51
8b0ab4e04aa6408822bc6cb0cef6fd34b5a2dc26
375 F20101118_AABWML woo_k_Page_113.txt
cd668a6e26ea3fe457b5c015e5076bcd
680cd89fbe295c7fbbc5ab45a5d6bc3496b3b8e6
1898 F20101118_AABWLY woo_k_Page_100.txt
86dd157dfe5fc4643464a4e08367cd65
efe865f028ce97b90c89e5f609e7c25d985d552e
1016535 F20101118_AABVUE woo_k_Page_089.jp2
344255e131d7f17e786b14caa0b074b6
402b026e56a415428f1ee50134d75041f9158d43
2174 F20101118_AABWNB woo_k_Page_130.txt
b6581127646a9bc2410d7062ac91a948
337ccaf6e59d95508319a8f5186013595483e5b4
846984 F20101118_AABVTP woo_k_Page_072.jp2
39837332c1f1222e6f4c47e85baacc1a
1cfc8cb8bdd0c6d8adda79e15c2ff70bd568bc89
390 F20101118_AABWMM woo_k_Page_114.txt
bb34c2d91bc463d65a04a08f638d105f
6b5d834a4b20488d616bffcce6a97777a3819626
639 F20101118_AABWLZ woo_k_Page_101.txt
a1561761aa351f384cdcca32625169d8
ef037b6f8f8504896f2470459a41542c69370330
682909 F20101118_AABVUF woo_k_Page_090.jp2
4736e445c44545933e4680fa512b6e8d
ce9b3456d9e3c8eb2f6e668133729ee06f15fbd4
481 F20101118_AABWNC woo_k_Page_131.txt
181e236b081737f4abb5f0e7beb7b68f
d4a4949402d1ed89393af21b8c71430e44336230
830050 F20101118_AABVTQ woo_k_Page_073.jp2
920423e15b86152b7764f05e0e4d45aa
1c44e8243ef5ad8ab7a77b1dfb4e77839db6cf00
364 F20101118_AABWMN woo_k_Page_115.txt
b8d760b1e00ebc825bdaa18a0979ebf3
ce3e9e636e45a8d3303446e34e7b4ad45138d7a8
772314 F20101118_AABVUG woo_k_Page_091.jp2
dfa996c2557f1d57c0efd8b385c5b41b
c6d2500afe5c22e0b7a6cf72ada104513a1e3242
810804 F20101118_AABVTR woo_k_Page_074.jp2
045e4b4ad98cdffffd5fc68bd35aa00b
893aa679de4c1e649b08270a66454bf7df3e488c
25271604 F20101118_AABWAA woo_k_Page_089.tif
90a7f61a4193e0eafc2e75c974eeec79
1623041d5a227fec90883d828e619ab82acd7024
400 F20101118_AABWMO woo_k_Page_116.txt
ec4dbd8bcb91eb145ce1803fb7c94416
1aa1e732d21de5c61cf32e4508aca0c18511fd1d
2119 F20101118_AABWND woo_k_Page_132.txt
2e43ef589206c34bd0c7565fed46e955
1feba75efb2ae08ffb9b44ff413649182562f59f
693249 F20101118_AABVUH woo_k_Page_092.jp2
943da8cdba22c3f378bc4b0cbd4b687c
60bd393bcac64b95eaf67084915bb903620fb8ef
990040 F20101118_AABVTS woo_k_Page_075.jp2
df8b6eb126ffd805e0cf5a26dabbad09
f10c03c5e21969f56f59f734353629c742c7f162
F20101118_AABWAB woo_k_Page_090.tif
80b0c0bb3865adc6779436afbb4720dd
55cd536c65784cedfc0b18660f1742a86f5d0a6e
528 F20101118_AABWMP woo_k_Page_117.txt
445fdc9f0588333a26c8d1dfeb37522b
239fd87a3719e38fc0f8c19b625796f0011cdd88
503 F20101118_AABWNE woo_k_Page_133.txt
cbaadeafdf1a137479655e2295717e09
e254670492788b18225ae23afbb0e6f9e9636012
833906 F20101118_AABVUI woo_k_Page_093.jp2
9e9907aed9f12b0cb10903d0475c1e33
9920329922804da902dd31e7ff02422bd99d656c
103828 F20101118_AABVTT woo_k_Page_076.jp2
1d101150d04c53af1743d910b005503a
621a524bb1cf06f24d682522e5c8b8c88285aa6b
F20101118_AABWAC woo_k_Page_091.tif
7ff585ac9c7a4423ff53623eecbe7467
265c653c1675e545defd91aa28c0a82e36841bf9
F20101118_AABWMQ woo_k_Page_118.txt
30ee915f064127a5b0ed32a4c700bc10
b0012192741d5ffbba42babed780e5edd2ec63c4
1893 F20101118_AABWNF woo_k_Page_134.txt
1178e4d9426c26061129a81d8d85e96d
3ce11d0d4426102c75196ce4993166e3306c9ce5
98920 F20101118_AABVUJ woo_k_Page_094.jp2
c7da85389159e02913339e13cf1674c2
f6b78adecaf7763708a2de8ba70c28d233983647
106165 F20101118_AABVTU woo_k_Page_077.jp2
a6d215580062ec3a94536f2a1493bdf7
a029b8e6082b56a8e7e0109101393be2554432f5
F20101118_AABWAD woo_k_Page_092.tif
a9f1c02902d2b8532895363b49ab35e4
f55be29d706c991d3ba40ef42ee212966a486908
197 F20101118_AABWMR woo_k_Page_119.txt
8a20482e6b740b43cee3bae0d86a14e9
72e6a2a9cd3d4655b2b7895904682bf4ebc3aedc
530 F20101118_AABWNG woo_k_Page_135.txt
aa054d081aa51db41fb596c282bdb097
2185ac68c4b86272935b6ba932f8f6c17dd3e837
93760 F20101118_AABVUK woo_k_Page_095.jp2
ebb8698c27797a12a02470a91c5b9dd5
973c4e534e58f7ab15a795c14bfd7751f9721f6a
662748 F20101118_AABVTV woo_k_Page_078.jp2
45d1b14fe9787117e8b69913f127852c
7ab9581192f61c97ce23f92ffbbbc36d9394afd8
F20101118_AABWAE woo_k_Page_093.tif
311e7530ad06179f60f8e22e1d38fce6
dc1a2d14a37f079d5aa89b7192250c38ba59d894
517 F20101118_AABWMS woo_k_Page_120.txt
236d2fc405272df62324a2adbb9df0e4
82898659b98702236a1f1f326e149e699283455b
2297 F20101118_AABWNH woo_k_Page_136.txt
1e47f53ed0d54f1f73e24051d3ffdf6d
7c640480d547cfddb32b9580cc6bd8199208ce9d
641668 F20101118_AABVTW woo_k_Page_079.jp2
87d963bae7f67c0edf4cf3fdcf515103
333be40535cd73fac3b4f1a1b3f03838b5370656
1053954 F20101118_AABWAF woo_k_Page_094.tif
d7b7f6e20ce46844142e354b5404e252
033986edf94aebb956a5310997879d72226d8eaf
1217 F20101118_AABWMT woo_k_Page_121.txt
1b458f48fe227df923e90ca5776be3e2
e9e15bfaaf490d29984f225f5514302a5cc98c94
2456 F20101118_AABWNI woo_k_Page_137.txt
8f3782ccd7ab157833d676ac55572140
d0ef5bc49e886fa603b3d5aab2d61de9a6dedabd
111199 F20101118_AABVUL woo_k_Page_096.jp2
a8f6230e94b1d598c62ae44c73d29586
7891fdb7d8b0e30f384b8c129918efe8b36a5c57
29741 F20101118_AABVTX woo_k_Page_080.jp2
1d81fd5f26c8f1e9ca59acb64815d8b3
d02f09c1f39b1f09fbc9c75e31f3cea6da6ec150
F20101118_AABWAG woo_k_Page_095.tif
afa8057b41476945f23538844080e242
68d771f00403b5ebe020316532447387bdf933bb
788 F20101118_AABWMU woo_k_Page_122.txt
edecdad43747163c88dc3871d638f967
6b7122b1f4399677a2b526910e47d61de6181eb0
389841 F20101118_AABVVA woo_k_Page_111.jp2
63a1d653685a66094026c9db5dfbf6db
600577a9e23e5bfcb818e927e6e8f8dcd5d400dd
2624 F20101118_AABWNJ woo_k_Page_138.txt
3a18edd7ecc5b95d38446599beea3623
603e4b8d8dc3ee33f39485ac28b6f853baf659d0
105087 F20101118_AABVUM woo_k_Page_097.jp2
8a2e67ae5203c5452fa4ffb20326fce5
2d03e53f6861a7ba8a92874022df1c0c46ec1ea9
83419 F20101118_AABVTY woo_k_Page_081.jp2
3a1c90b88bab9b245c554cc16e7ab98c
7ba7ed349a7b1aaf2b360042e40a2bea9ac42574
F20101118_AABWAH woo_k_Page_096.tif
d02ef46803c96aab2b514ae5a8ba3e84
b7612597edc2e9e297855d20ee4fe3149bad6863
211 F20101118_AABWMV woo_k_Page_123.txt
2d27080c56f17e6cc8b12a8e0a9904eb
eb111e4e55c58040283a85071c8905934f65adf0
242335 F20101118_AABVVB woo_k_Page_112.jp2
cb049e8e27aa3a1a59c3d6cd1e3280d8
a8cadcd8bda03cb23fad9bbd2ad598e0d2c69a4e
519 F20101118_AABWNK woo_k_Page_139.txt
70b5b6add42dd517ee5eca3cfc89891a
012e7e971aa790ba0b9e0810fe50aeb59fa0590a
110543 F20101118_AABVUN woo_k_Page_098.jp2
5d66af7c45e25a6e24f3c80a0bf3d5e6
dd20661019f2b65ad4d1e04a1b710e67818073ef
90741 F20101118_AABVTZ woo_k_Page_082.jp2
29774a1ecea474b437a6140da087a47b
1de9630427730e2b5a5ad4038f118544a5ca52a7
F20101118_AABWAI woo_k_Page_097.tif
23b6408d16d399193ac248a49295819f
0bb80fa7806d67beabcf8d1e085744e4d70b27e2
2115 F20101118_AABWMW woo_k_Page_124.txt
b68b7b0b42e0c2cbf7f8a7019d2a536a
1eed808b2cee5d74b2f01aa5ce10b10ded169cae
244921 F20101118_AABVVC woo_k_Page_113.jp2
70d9251c292dfe7d5333291a190e0279
68f495a8d5fbeb033e1493998bc63ca7ff7c5f4a
1531 F20101118_AABWOA woo_k_Page_155.txt
14e018eb660f196abf183ff219037994
a2388b037afa2d54bcc620ffeba5a618ccc034b7
2072 F20101118_AABWNL woo_k_Page_140.txt
c2d872c4dd53f65253dea2cd7e3b3a8b
5a760a7f05bdf54495d9c8928642fad0e4ef8847
107867 F20101118_AABVUO woo_k_Page_099.jp2
9ea4da10242d1959b19bbe7db93946f7
6fd3370df776c25d9c3048570ec49bbd608f557b
F20101118_AABWAJ woo_k_Page_098.tif
4f83864ed9bcbe24b05b8ec2a63d8274
ea6fead735c0bb68275150de9d5b380cb1ff4043
220 F20101118_AABWMX woo_k_Page_125.txt
38af0f77e9aca30b7d3a776213d594c7
d499a58f810d447442407a07ec661d124c5ed3fd
244340 F20101118_AABVVD woo_k_Page_114.jp2
f9a0b80ec3c627688ecfed9071a5b4f6
8132ddc9025c6c075e8b540f09cd933def726e9b
1934 F20101118_AABWOB woo_k_Page_156.txt
5f81b15cab1e7b5a080c94241db1a023
4a415b259c132b14fb8fdedcb63ac0b7a9104804
2531 F20101118_AABWNM woo_k_Page_141.txt
25eff33237dcff5c1bdf3d567be2502f
ad8338e63bf3f490cc8c9e44ce95c16bfd1850f1
102945 F20101118_AABVUP woo_k_Page_100.jp2
1e45ac95bc9f0c65282c6f35d8777d8d
4132b1a6ae805abb69cfda248e161309d7a4bc6c
F20101118_AABWAK woo_k_Page_099.tif
4e2e00bba94ef65639290c12c1ce615d
0858e30079a19a60c7f1b191eca8eaa13f915d91
1669 F20101118_AABWMY woo_k_Page_126.txt
fba97cd48d0d41527fa905aaadc43dda
d7a898e932232121b4b5d272306b97606e5f7bb0
240556 F20101118_AABVVE woo_k_Page_115.jp2
e4f93c85659dc37588187dc5af25d700
f34d5a74df97a23eb062e2e02b84a1455f493117
2030 F20101118_AABWOC woo_k_Page_157.txt
384bdc4df7811e9bdb3b671a8c3b9ed6
c8fd721d9c2e0ae25a2db631469a4dd6d60d337d
1194 F20101118_AABWNN woo_k_Page_142.txt
6549be32899cf0796b67e93c0eac5233
f5152cbd4c6d7b41a23bc390edaf924b1fcb80f9
35151 F20101118_AABVUQ woo_k_Page_101.jp2
0664a37eda81574a678e141848010d26
3fdd5f7a9a52a9a7db510e8b0cad6690a300add5
F20101118_AABWAL woo_k_Page_100.tif
02da9e065b1d5ac183b882ce2edf9d77
b322f2d969d2bd083279f251bad3a3c8accc009b
330 F20101118_AABWMZ woo_k_Page_127.txt
183363563af03a29d89bed654b0d2f27
24c1f7f819ce98b1a2d739b46373b8f3099c49d9
247415 F20101118_AABVVF woo_k_Page_116.jp2
22ebd9568464453ea898db5988349937
d86f8db5a8a276cc339e0c47e985712dc9adf660
840 F20101118_AABWOD woo_k_Page_158.txt
6538f81bb9d570db172f2fbc6780d679
3b68c462462335406c6179e2aba68d08af1b5b81
188 F20101118_AABWNO woo_k_Page_143.txt
fd971f67a7589bf41f5d14b4504b48ba
26d3bf6c48ebfe7edbaff459d2df5bf5a09c8124
539614 F20101118_AABVUR woo_k_Page_102.jp2
7269a91640b65e2e8b495ba66fad399a
a7b445f500fe19eb766cfe041ec97c5f78ee2c5d
F20101118_AABWBA woo_k_Page_115.tif
64abd5ce9a4193fa67fe66ee6a3d4051
baa4e63d202bbf9775723f951f37b797bb3c1684
F20101118_AABWAM woo_k_Page_101.tif
92018e7acd3d5e8f385937a3fb11d00e
128e7c2d2ddc3fc8d30ae517154ea44332da4ee1
437336 F20101118_AABVVG woo_k_Page_117.jp2
db36a719652310a0d4dc193c881c66ca
f7da4c60347227ecc66cec7b66656ee436683745
1167 F20101118_AABWNP woo_k_Page_144.txt
ee4ed7a47d3345841c7cebc57b477acc
bb4c00fd0060554853187db23cf1a4892df37481
583748 F20101118_AABVUS woo_k_Page_103.jp2
860688f0b3c9e4f1d709522ffd277bae
51c61d4e60985d482a8ddd46cadeee3198a98352
F20101118_AABWBB woo_k_Page_116.tif
8f36146861f911fb092daff057e53147
5c1e74ec78e1a78941423502e67cea4546493b7b
F20101118_AABWAN woo_k_Page_102.tif
fb1bdb2d016e0b7193754501063c41e1
0b0dd65ed2c32f8cd675f625354f4538e874bde8
430563 F20101118_AABVVH woo_k_Page_118.jp2
5a7b8b6e3329efeb445f71ed01ff7986
48f70fdd8d8e550b8e15ef6cd8568d09d6999793
2263 F20101118_AABWOE woo_k_Page_001thm.jpg
da2459d54de25fd83996fff0314db1aa
699b20de65416cb64596c1806bf51d9b09c750a4
2295 F20101118_AABWNQ woo_k_Page_145.txt
a12832c59b4f102aa779f88e631aa561
a2999a44bfb3537e7525466cb70a76c1991a8cdc
93970 F20101118_AABVUT woo_k_Page_104.jp2
82d68d6db36446fffc18656707b5018d
7b7152c311e1388263faa4402769d587489dc593
F20101118_AABWBC woo_k_Page_117.tif
199fec53a9177ae4589b11cc54bddcbf
196656b69b6987b46192932a19f6bd6ad1e94613
F20101118_AABWAO woo_k_Page_103.tif
4c92af942807af1ecea95b36a4f2c6ee
377a5872265ac2d7088fe1508595d5506e8ac0e5
397087 F20101118_AABVVI woo_k_Page_119.jp2
be5e905d131ddcf81b0bc43fa05cd9e0
3c146b773f5a348af8b3bac8fc4c938394fd7ea1
8118239 F20101118_AABWOF woo_k.pdf
791e8c47961cc329ef8244e601bfdfc3
1719addc1709c605cae1c883067d73f608e8fe7d
377 F20101118_AABWNR woo_k_Page_146.txt
67ec7f638e3b1939f112d82854960096
6071bd9bb1754b7aa1b4b20a005a48b5c79fb198
109604 F20101118_AABVUU woo_k_Page_105.jp2
f343f1c881a6923ac580b4d1372d8cc3
43555f3f29860e6a89a2ddf85fc15073e7a8e32e
F20101118_AABWBD woo_k_Page_118.tif
63e9d04c97c26383ee39c83f50e626ab
012ef63eb0a9a0701224835982acb5ff12c5f39b
F20101118_AABWAP woo_k_Page_104.tif
ab33ec58b2079e2de0def8272f0d394c
a856c4e5084b3bff7539306d01f96ed51dd2bc95
362018 F20101118_AABVVJ woo_k_Page_120.jp2
0f2594bba1a0c2901c46fa66d0887aba
564fecc1f1de6efa53c388a215e7cd833a0c8cb0
7177 F20101118_AABWOG woo_k_Page_001.QC.jpg
f3787826d94d7ca8ddbaabc6759db5a1
c9e3e43966c5c1eb0a8ff04b1ac3216f088ae805
2022 F20101118_AABWNS woo_k_Page_147.txt
12c1e8b767109ae000f7097a7210ade7
f148d24e20257870248a1e08bfbdb727ce99dfba
103982 F20101118_AABVUV woo_k_Page_106.jp2
0629d0c57ca4a1d5f8e9e62e315caa02
623b13eba4cd0dcee4137261b5cfd32614934ef1
F20101118_AABWBE woo_k_Page_119.tif
f66301fe093da2374dfaa996de257267
fa80cf25ec7c0834f0e077a29fb9a57606a60ca8
F20101118_AABWAQ woo_k_Page_105.tif
e9e41c6bf76343653bf4f2b66802014c
c7dd7cc932d62b0ff24062210ab0415588f9862b
1051946 F20101118_AABVVK woo_k_Page_121.jp2
dca8bf5e1e6b56368d6f0791b28b1f49
1e16bf48ed51ebd9dc389382ffc96352d7bcbb42
3280 F20101118_AABWOH woo_k_Page_002.QC.jpg
ec41d5d54ea41692c72282ad23f47332
777397248e5507dc44f54b89e5074afeedea7ef5
369 F20101118_AABWNT woo_k_Page_148.txt
0162fc72ec6e34bd7062a1d03baf747a
16467513cd64d2c97be391f9b3a7dba02c0c3760
21546 F20101118_AABVUW woo_k_Page_107.jp2
874a527d464ff6068af189b2bef337ef
837c007409915a723866b2b9be32d9265e80cab0
F20101118_AABWBF woo_k_Page_120.tif
8539e354cb02806d4633252ef06d6fe9
8fb0f0d30e55c2c683ffb1582e4a58e9a652bfe0
F20101118_AABWAR woo_k_Page_106.tif
80767fc8259aa72b1e62c2db1e125ef9
5e9820f87b6c5fcb778c06f7ca6e0e18977d4f5c
275482 F20101118_AABVVL woo_k_Page_123.jp2
28d0b2cb580f598204a6d4d635160d8a
8712aded09becce6143e516b7ae1d8188c7d995d
1371 F20101118_AABWOI woo_k_Page_002thm.jpg
99bdc17fed8815e16fb4721eed47cc92
0efa4406889efe85601cfd56f135b1e011ccf95e
98 F20101118_AABWNU woo_k_Page_149.txt
b95dcbf6095b6187d00196789b5b9608
13164b15b93962a16180ce970a9182772cb3bf57
417488 F20101118_AABVUX woo_k_Page_108.jp2
b8e9b3a311eab4d5f7e5133d5181638b
1457e3e8aeea6e8e20b495457d6e2524968be5f5
F20101118_AABWBG woo_k_Page_121.tif
29a5147ba5c655734b41847cf33169be
d544ac3192810ed55768aa352b260e7ec294ca5a
466589 F20101118_AABVWA woo_k_Page_139.jp2
9452b035ce0d0dfcf504d8ead7b3567b
893a4d51c6f623edc889d9b5586ce002a29bc07e
F20101118_AABWAS woo_k_Page_107.tif
44e9ae7adfb02821375f2a2986c680d5
cb67aa658b1a1a7e32eea3a1d40fd38b2001ff99
4904 F20101118_AABWOJ woo_k_Page_003thm.jpg
cd86e59e6ae04171b3ed3afd4ee7e166
89d55b302d2fcc5bca8cecb0cb76fa00f9d9c620
F20101118_AABWNV woo_k_Page_150.txt
095bfdb074ef066d30a3fa64b872fc83
5183081e1ad861687f2eacd68df03234a386e3f1
373060 F20101118_AABVUY woo_k_Page_109.jp2
5314c48e18674fc3ef127852a8b04ce1
4e89490a012a1cb5c21938041f29739c3edc2c54
F20101118_AABWBH woo_k_Page_122.tif
e478e42b46708e34dedd23ca9df6d466
809b805f6b94e660db91522fd2472b43d0210e30
1051950 F20101118_AABVWB woo_k_Page_141.jp2
b00ed2e0f41dd07bcf75f2ac353d50ad
a8e448aba96137713b1ab1ba358c03086b5c823c
F20101118_AABWAT woo_k_Page_108.tif
a7a92298ef65e0337be615fc37cf4004
9456665561bcad914975448d2036221bbaa9db4e
1051985 F20101118_AABVVM woo_k_Page_124.jp2
0726d2afe31c82a140fadfb6d6e14dc0
2d5ac07c4d77c4edd3ac1d2dea2454c086bbc9f0
19298 F20101118_AABWOK woo_k_Page_004.QC.jpg
1bbd6ac56c915f95f8fbc501f77a5ddd
4e9e6fdaafc51205dede24b7a58dd92a41b6a505
306 F20101118_AABWNW woo_k_Page_151.txt
db7c94799c6990032af4337b8810271d
6ef7b37519edab3a7eeeefe1f7e3a6f1ec912c47
322918 F20101118_AABVUZ woo_k_Page_110.jp2
5ebe2a998cbbb59a420b9bbccb44e582
6a9312f1ecd0d6b75113e8384bef9824a7e11403
F20101118_AABWBI woo_k_Page_123.tif
86eeb2175c1bab3574bd6281ef6f7fe2
05d0e883c5024612a52d595bd77d6ad934504f87
1051980 F20101118_AABVWC woo_k_Page_142.jp2
299e48ae108ec285a3fd75ffa17f681b
7185811f1a62d7770c07a66b0d10c108eff803cc
F20101118_AABWAU woo_k_Page_109.tif
5f0d93f7f7596fd0a902decb5f9fdf1c
0cc1bef940931b35da75200ceb2c60c4b50a2cae
1051975 F20101118_AABVVN woo_k_Page_126.jp2
142acf206c53b074191a7ad2ec10163b
17b3687fd149d4edc039fd5bf8c9d2a5011a2f65
2998 F20101118_AABWPA woo_k_Page_013thm.jpg
0be7efb38b213de1306fce44bf6dc0ed
42d0e0a25f7c7fb205e821ef8d0f1677bdec4374
5027 F20101118_AABWOL woo_k_Page_004thm.jpg
41a4a8b259f9c8f2f8000873f16f912a
48795be87f3f64a28b7b39fbe75ded47a19237b2
236 F20101118_AABWNX woo_k_Page_152.txt
cb5b4bc922d872b251638c626f330f77
1f7b5ae4d22d30fd262d6151b1086d5defb3d60c
F20101118_AABWBJ woo_k_Page_124.tif
f12cd709a10c8914b56437cb81c683a2
a5f62af0e11f973f88361ecade2109f3744a1117
460107 F20101118_AABVWD woo_k_Page_143.jp2
ca521e73634142ef80716c0c10d2527b
2e207347b6880d90b5fb50e7b1a207d673e80e37
F20101118_AABWAV woo_k_Page_110.tif
a6fd1e3e58a5ca5649ccfd104bb46c3d
2ccd6cb0f563bfc2987ca0958d57028cb3c2e510
267697 F20101118_AABVVO woo_k_Page_127.jp2
17863f9a6d91769b05441cfa64d079ec
378d0dd6c5d211bdd4482435c245708efa09ef2a
21036 F20101118_AABWPB woo_k_Page_014.QC.jpg
3cf9619642f8762e4de749700542d88a
28a6aa249eb9414bfc4b6ab817d8e1ca480e30fa
24724 F20101118_AABWOM woo_k_Page_005.QC.jpg
0ebe57f2582628748c67747d962ecda7
da95fbf723e4c90f9074ca5313ae311fa2646e2a
404 F20101118_AABWNY woo_k_Page_153.txt
5670d1858d6858e2d8e502b223d49c0b
72ad652a189f666bf529520bb532919ea7d5ea27
F20101118_AABWBK woo_k_Page_125.tif
0057362cfdb27b89f345b069d7fbf6a6
becbf9aaf1e87f47fbb081a620902414e3820d2d
1051971 F20101118_AABVWE woo_k_Page_144.jp2
0606b07721a6d7e68677c1921523c463
7406ae69706abc7f0aa2fe526531a9c2925b91d6
1051960 F20101118_AABVVP woo_k_Page_128.jp2
f6b93adcdf3586250993d55e6bb74636
05e26342222a98014e4c8808f17d20a84def0eda
5876 F20101118_AABWPC woo_k_Page_014thm.jpg
38fb9ab23ad4a6d7a535953c2e2efc38
8ed066bfcbcc7df0db95ac0ca9673591c2e7fe12
6281 F20101118_AABWON woo_k_Page_005thm.jpg
f22f79f7799a5221038c928062f1003c
058e1acc6f25068b23540c8c778be23d1e94f154
F20101118_AABWNZ woo_k_Page_154.txt
be14c26eb67cf58abd669d497b8d8326
4829e57500a9399fe331c34fcf860a4cd4ab87ca
F20101118_AABWBL woo_k_Page_126.tif
37890c4c6b4433ad1c773d7395e3adc9
ec7f47923190f116e2e2f5e57e92d19f68618c80
1051984 F20101118_AABVWF woo_k_Page_145.jp2
418ee322cf45d74b103b9da6151efdf7
1f95f32dcf2dd3c7de9e251ac524774d183f8fc1
F20101118_AABWAW woo_k_Page_111.tif
f79f91d584103e1a07bfa86e374a9ffa
72ef87fcd751e55be817acf008ac1a49ee844aa7
269105 F20101118_AABVVQ woo_k_Page_129.jp2
42aaa0c6003c3c51e9ba5a920178de1c
920eb8c89182c853665cc7683f32cfe8bae0dac2
22589 F20101118_AABWPD woo_k_Page_015.QC.jpg
ff7142ea13b27780031d83061c7a3c1d
fc32bb241e2dfc440f8020ee85b56c3cc1f11879
2301 F20101118_AABWOO woo_k_Page_006thm.jpg
0382c32831661ffbe87fb3fa2036aae5
44a1cf888afba141f90800644c3778ea05e83cec
F20101118_AABWBM woo_k_Page_127.tif
abc0f39a4ff5e5f589a14a0384875c98
32c213166e6f9283ac2747bfcc47de8554397fa1
317430 F20101118_AABVWG woo_k_Page_146.jp2
a34a16b33fb969e0a848d5e8e4b547e5
e09bbcb8b99579d763eb66aea6dc3ad39efa75b6
F20101118_AABWAX woo_k_Page_112.tif
fd24a8031185ba799028ff05b16a6ce4
01cbf3b0fff252d6c178f9246fc83fd09b5e4113
1051899 F20101118_AABVVR woo_k_Page_130.jp2
27a8b669699019bca221166ac2c9cc66
3730acdce862422856a1d9662ec8cc49c553e02d
6366 F20101118_AABWPE woo_k_Page_015thm.jpg
5a84975f0623f298360add16d5b2bd00
29586e141951b29aa4fc5a64e3d41e77eb082236
2623 F20101118_AABWOP woo_k_Page_007thm.jpg
2729e8564f1aa490b28ff62a5bf1db2d
06dabab9172249a836d3c86343e18fffb3fbd92a
F20101118_AABWBN woo_k_Page_128.tif
e91bc8caaab03d61e7229b5172146207
d58879b77c96f1ec0962cbea064bda03ce20aaf6
1051941 F20101118_AABVWH woo_k_Page_147.jp2
ad2bce74181b4505d5326ef384a51686
39b594ea9f9ce85de5ff2a4d9b844517039d2a40
F20101118_AABWAY woo_k_Page_113.tif
ccc149d4ba05b0a7d63b5a5fd5a05f67
155a70016a3c24371c31ce7b4a982411d53a138e
284915 F20101118_AABVVS woo_k_Page_131.jp2
6ae1bf93018909beb70c79769cf3bdac
6fd9a9f6eb9e3184b87b5fbd5b287d870f3b718c
24073 F20101118_AABWOQ woo_k_Page_008.QC.jpg
3752ee6d4098f196087b9bd5f7197e76
5a3ef15bb2ce418ade053b9c7be6bb725715b508
F20101118_AABWBO woo_k_Page_129.tif
85899ede34581b0ebe72d250b538820f
9a7f8cccc2326f472f300f6580607a3a1816e556
311615 F20101118_AABVWI woo_k_Page_148.jp2
7a4dd35589b4c9fd4980c75542d941e1
5f1bdd3efba09880e447140a46be96f98ded3a95
F20101118_AABWAZ woo_k_Page_114.tif
c9c09ecb0f842c8b947f3e68ad345703
20dc348c4774c2d02ce4e8af7b9c2ea29edfa59f
1051973 F20101118_AABVVT woo_k_Page_132.jp2
40b6a3f7a3bcbc68391eb9f125bc3385
cd1bb249925f3edfd6fa0284a5f05d40adf07e59
12517 F20101118_AABWPF woo_k_Page_016.QC.jpg
83b81184576fd276dd9a9b9a9cdff776
66f5e4afdb3441f86ec2f1c72f0f763fa947ec81
6333 F20101118_AABWOR woo_k_Page_008thm.jpg
ab4ea6f1eda70fc660439f66f4bf1d1f
71097f3ae5792dca9af789b5aa6bd6cf5f6a2444
F20101118_AABWBP woo_k_Page_130.tif
84830c8297bb88ab572920354f65e6e5
14aea690acf6f638d8786022d4da74542ebeb4fd
1051986 F20101118_AABVWJ woo_k_Page_149.jp2
68f7ba82d6c762b2b533f2a7d998f9bf
2a0a5ff06189d4666a3373e8a72603f4ed0cfa7a
301450 F20101118_AABVVU woo_k_Page_133.jp2
4fac4a055ce48755ad91881997fa1b5f
f68d6df9b4d2771ea05b24793794a48e2bc566b4
3747 F20101118_AABWPG woo_k_Page_016thm.jpg
d62b0fc00c585700309ca8854cf49861
8782ac3d120a596ecbe0e1fc1f352827f3ee4134
25485 F20101118_AABWOS woo_k_Page_009.QC.jpg
23e6d65eee1ae2bea89397d7d981794c
db469f77a2190c6da4d33f3416031cc9b12bb39d
F20101118_AABWBQ woo_k_Page_131.tif
667a2535bcd49fffde842697c5d88089
2dedf92b267b125f7b6f14ed642d25db4a38bcf9
386282 F20101118_AABVWK woo_k_Page_150.jp2
730c33026e4f79df0f3ba0db0556e83e
a7d4af091f507ddaac253ca6ad8064afb3e80a6e
1051983 F20101118_AABVVV woo_k_Page_134.jp2
d0c7848173d123bd7933c0980881384b
3435df1b700e3c82453a381c017a82cd7c140f64
21968 F20101118_AABWPH woo_k_Page_017.QC.jpg
9ad2c7d0f5725d092b4ff493b8e7a206
572ccc909d691fda5d369caf6edd62ef48c38354
7130 F20101118_AABWOT woo_k_Page_009thm.jpg
1921aa39f1b6602ff9fefa33c3b71f23
1ccb1f0827b2eb991ba5750714df09c53ddcfd6c
F20101118_AABWBR woo_k_Page_132.tif
13dea8929da6064e5c0dec513c3b278b
6be3cc0cd42ad2004e6fb97b1ffe2da445ff2d94
382477 F20101118_AABVWL woo_k_Page_151.jp2
1c6666140667457c74da84c4122aab6c
24283db27d441448e339d51e2ab3c805d00bf8fa
494844 F20101118_AABVVW woo_k_Page_135.jp2
ac2c09a1ab17f76597b3e78ddc83470f
03366c9d8b94422e59b7977bbe9736a5f530eea5
5744 F20101118_AABWPI woo_k_Page_017thm.jpg
8c4bb676a56104af3f07e1e5fb1ffddd
bb9e1fb5639d100be862f644097a854ec0996aad
27672 F20101118_AABWOU woo_k_Page_010.QC.jpg
050ea97ada3090be5be5836892200500
085b3c590d79dfbbfe276054f84e28ff5a14ef36
F20101118_AABVXA woo_k_Page_007.tif
cfb4d4579c2ac549ec9ca826c85f6883
c843272b994ee9e1a24278bdc1c51971193a0c49
F20101118_AABWBS woo_k_Page_133.tif
ff1ca10520eea17ae96532202956323f
97330422b5f0ae3d9abbe2f90f9d0ac49b855e6f
403196 F20101118_AABVWM woo_k_Page_152.jp2
fb31e670a39975d64c22ca0d6689fa50
205dfaebf167436300fb2dab9e0e04a640dfd15c
1051976 F20101118_AABVVX woo_k_Page_136.jp2
0067ee90f85ba7669c2259527c4b6fac
651c39474b473958bf2e2453fb1a6bc3e06b4032
6346 F20101118_AABWPJ woo_k_Page_018thm.jpg
33cc69ada16978f1d92d1dec0370bc2d
af844067806fe7b007a61df2c177bfd8181ba9e9
7036 F20101118_AABWOV woo_k_Page_010thm.jpg
38380a7267bbf40aea904298b74e2f52
75a9d4e5a66ce8333caca739c65ceda39489d98a
F20101118_AABVXB woo_k_Page_008.tif
460e147c2c7499198351f70b299f247c
c06365e99cee08f189ac555a4627deee83eb4756
F20101118_AABWBT woo_k_Page_134.tif
54dc16774dadefe5410f888534dbf21d
f46bc7d21ce62804a498cde7e41f3775699f48ff
1051929 F20101118_AABVVY woo_k_Page_137.jp2
fafcf9ba468163da8694fefbc675eb73
1449c309c25513492028a28c60637ab19b121f99
17184 F20101118_AABWPK woo_k_Page_019.QC.jpg
9d7d7f71871e017c322a30ad263c71bb
207038e69fdac8503d00b5f8dfe8a265c23ee999
5737 F20101118_AABWOW woo_k_Page_011.QC.jpg
9ce37138e26e79e601650ff10835f7a1
a0dc11909f2b8c179370997bd142360016f9c8d0
F20101118_AABVXC woo_k_Page_009.tif
b070dd39836436b7082d1cd58225d7fb
d411da690d9535a6d96830a221e483a7e4635cbe
F20101118_AABWBU woo_k_Page_135.tif
9b2b614fcab73b95d4f899eb081d6866
d80ab6343d209f0c03ecd8197fd6241b9b00825e
473405 F20101118_AABVWN woo_k_Page_153.jp2
7bf17cafdaebbe645311bfe2d44f2256
6b9750b1ff817abfed65da2ca8b475af7b2a9f54
F20101118_AABVVZ woo_k_Page_138.jp2
3d3a74b12a0c359a117dd7a0e8a8888d
b1e3cced5c993f689395cdfd1ea5dbbb39475569
15741 F20101118_AABWQA woo_k_Page_028.QC.jpg
bc0ba86946b2fc1c4d5287b5b9a130ce
0af8701c8359ab9ed4e7f6c0902951c120fc7406
5194 F20101118_AABWPL woo_k_Page_019thm.jpg
49a5cb1ffd0bc26b0e67c0b2ab0a111e
659d8bcacd0ca075e72026c06bc61c7048c6990f
1885 F20101118_AABWOX woo_k_Page_011thm.jpg
4587a124cdeefbf7b4d8d5f173b8a000
c02048e62e3ed9442cf63a79d162e36cd8848197
F20101118_AABVXD woo_k_Page_010.tif
1d0307729f5c38a47c61970b44f49f67
640010f05e8c5674ec6c61e897f663546389ac03
F20101118_AABWBV woo_k_Page_136.tif
d26fa4ad46bd9bc7bae423e7635f9e57
4b616b3c43b633838978829bfb6fba98ec72f199
527242 F20101118_AABVWO woo_k_Page_154.jp2
cd445799a85580d059159506fcb9efd8
d4126228ac08d20e3e738a8a98c02b1eeeaee2a9
4907 F20101118_AABWQB woo_k_Page_028thm.jpg
ee60ca427e1c5e8b44c90669f033226a
ecfccde8eeab728143fad0efe146151ba036d12b
21521 F20101118_AABWPM woo_k_Page_020.QC.jpg
a62c76bf34f43e00f6bcba8106034719
5c2bc82ddce4f7ea79ec4a19010b6f83c5e62197
5326 F20101118_AABWOY woo_k_Page_012thm.jpg
5ec4cb8a1df4691322a823877a60858e
a4a7207b02d2b79857b42e8dd6bc9236e0eed290
F20101118_AABVXE woo_k_Page_011.tif
f34e351c5c7dafa47e9e83ee169ca903
8572b947c7726727d9f3d340d44ad5edc004baa3
F20101118_AABWBW woo_k_Page_137.tif
e61604fff9723eaefa2e27e82efc91c9
e46b708adda263664f1c0757272b51ff709a9bbb
79907 F20101118_AABVWP woo_k_Page_155.jp2
bd8ddcf3cb80c7a481339af5163369bb
a459bec7af8a7fae251b8465683066288d647ff4
19763 F20101118_AABWQC woo_k_Page_029.QC.jpg
d1a4e8853876f0c9384ed6c658f6912e
aef40b8dbcb328b695009ee2ca6c8d8793e35df8
17530 F20101118_AABWPN woo_k_Page_021.QC.jpg
1d425a38d9e2fbc40db530ccf9ae562a
41d225b8cfdeff8fe5dd0c136d8d543528ededb0
9711 F20101118_AABWOZ woo_k_Page_013.QC.jpg
14f8d223b131485dce4225ca639b32ad
dcb69cc17c8a47ffc7039305ab28e5cb818aef94
F20101118_AABVXF woo_k_Page_012.tif
58d9f22e1567ad8aaf39148356e0b1dd
2612fad9c2e523614abf96e4fb1e9f396088663f
96905 F20101118_AABVWQ woo_k_Page_156.jp2
6dedc8374e182a9c30db17243654ba30
b11eae11510d244b15bf6a0bcd13db7f3e74eb63
5806 F20101118_AABWQD woo_k_Page_029thm.jpg
4e134a962b3e972aca976d5088386848
0647b112a0a449b691475730cc139c300651df7e
5452 F20101118_AABWPO woo_k_Page_021thm.jpg
2b3e0c64fb7b4cfb83c7568c3d74be03
36fc700aa0e8e2b3d666d43c62e10af19234015f
F20101118_AABVXG woo_k_Page_014.tif
c1e9031ddd83de9a316715124e95a4e9
3535b3805b92f3de036eeafc33692acecf00f742
F20101118_AABWBX woo_k_Page_138.tif
d3f16730b442901b5b18928454765b47
85d3995122512e73063b820abc2f54e5e819e202
105328 F20101118_AABVWR woo_k_Page_157.jp2
933b3efa423af2e014c8628db7233adb
bdc8615f9591a17c1320431b394b0bd46ebe60df
22311 F20101118_AABWQE woo_k_Page_030.QC.jpg
8914576ab0c0a84d2836a1c085e78f31
6d3455559ff963248e71434325267ef26c9bbb8a
12649 F20101118_AABWPP woo_k_Page_022.QC.jpg
0dd51d5bf4acd5cd69f901379674defa
69a532b6b2ac54f328b192f35dad38b9671774c7
F20101118_AABVXH woo_k_Page_015.tif
c3d8d3c55da70af0fc464a1968441118
2c5425142d12079a92d10eb2aa09ce7e872caac4
F20101118_AABWBY woo_k_Page_139.tif
801f9af78069295946550da071ed6c5a
3c977ffaa7ca91e1d3a24d55da97f5b362fc5880
45964 F20101118_AABVWS woo_k_Page_158.jp2
2a25fda694086095a9324844381c9a2f
c1308c3c1fdbdfbc6cd3cf94dbb6acb435c47ad5
6398 F20101118_AABWQF woo_k_Page_030thm.jpg
d1eccbe7b859f0e0e8d301c0a9da4511
4e3902e0ec3439d7fa4e33842a3015f3925f052f
4371 F20101118_AABWPQ woo_k_Page_022thm.jpg
a5171cea4156904b5393ba8bbec56228
c1e0221c99fd49588363edbe80985f4a0a1a3b7b
F20101118_AABVXI woo_k_Page_016.tif
299a77805b0b3e47e49404b1553efc3d
c07465c7ed3ef5ee331afbdd6a5d0938b945c2c6
F20101118_AABWBZ woo_k_Page_140.tif
a1a252eb8128f4546b1f8713175200e6
2a7308f2713b557fdeefb6af01dc83e0024a5e9c
50170 F20101118_AABVWT woo_k_Page_159.jp2
5c5d07a4e224295bd4505d772cf7c4a0
d1a3d1c7c38b1ecdf7f0edbcd491c90c2d65c01d
13272 F20101118_AABWPR woo_k_Page_023.QC.jpg
37ffc9088e14eb02a3a92b38e5cd696a
724112d2f9350d67b997688b7d7d3ecf642626c8
F20101118_AABVXJ woo_k_Page_017.tif
d48dca93e4da7dbcbbb307819643ded4
01c292de7be1b69fc369d9e6b0139af0910f8ed3
F20101118_AABVWU woo_k_Page_001.tif
9f1b51efa13a5c09904140f67e177942
967f16203bd4c4a5a7d997c9cb2b83ab653d3b4a
14164 F20101118_AABWQG woo_k_Page_031.QC.jpg
6e1f87baedf4d75e95d3cca146c13812
0eafce32cfbeb091df6b29e5456256d57ecc4031
4326 F20101118_AABWPS woo_k_Page_023thm.jpg
4754edf24f42a4a6f78c38df91cf75c7
b81c754e73d6cce2422ff95287757b04f33ed50d
F20101118_AABVXK woo_k_Page_018.tif
f7fd8dcb14e2c06aba66e03c1d304aab
fe7d0d892db41062266092d46a1541acddedfe94
F20101118_AABVWV woo_k_Page_002.tif
4cada7ab8fbfe077c94b1f5bd69739e6
239f89e26d8e0348502a163f622a7ce5e4da14fb
4458 F20101118_AABWQH woo_k_Page_031thm.jpg
0d414f745fc571f2905635f09d7bcb2e
fbe57014a9c8e2472d7a33b128f384d83522036a
13333 F20101118_AABWPT woo_k_Page_024.QC.jpg
8146209c2fd679117b62b732d557a35e
d7239f5f00cf5d57ffde7ed5a369aff950ccfc03
F20101118_AABVXL woo_k_Page_019.tif
5aaf009d428a899954f322b0de91ef47
9035f7838db427af2c4c7635bfac5079befa75e6
F20101118_AABVWW woo_k_Page_003.tif
e013d56dda7858a8b45e966aa96708dc
0600abc9e2fa3b668a5a1afdd2caec69248f0270
21084 F20101118_AABWQI woo_k_Page_032.QC.jpg
aa464c484773383af5bf7480dbba7fb1
43cf773b55997b5e5b6f2cc438878b469b720b1b
4549 F20101118_AABWPU woo_k_Page_024thm.jpg
7e5a5fd3db5ebe60ea44ac7ee40bdf6d
4ee04ba5cab939bd8ffdddb32897bd7804b2862f
F20101118_AABVXM woo_k_Page_020.tif
08bb50c5fa489d3a7e580aed3d087492
7de27d446cdba2b6f5d386248eb5731aaa8ee64b
F20101118_AABVWX woo_k_Page_004.tif
eae894a91b91e2409fb51a6de6c99529
1a44be4a10fbdeadb5c7b8f452d0d5148938bfcf
F20101118_AABVYA woo_k_Page_034.tif
8808a632cae9c607ffb2c625236479b8
1e29a0f6b9a71ab82247d483db370d2efce0ff08
5889 F20101118_AABWQJ woo_k_Page_032thm.jpg
b574efa54f047fa7e44a2080fd88ee91
b184f9e39e47beaecabacaa618464b5f1fbe3e6d
12528 F20101118_AABWPV woo_k_Page_025.QC.jpg
1e640c39ba738df955ca9b7ce46f4666
5a6fa3464ef544e8b456943a3a706a8eba171f12
F20101118_AABVXN woo_k_Page_021.tif
1c455c574f7c6c670db8a35d47679e47
51833a9148b61cec625d85a4ddb91bd93c01ed60
F20101118_AABVWY woo_k_Page_005.tif
2370115c67242b3c9442fa9f9d3122d9
81fc25590a703d1495e0d22971eece3e99f49a58
F20101118_AABVYB woo_k_Page_035.tif
ea5ce90680ad84fa04d04299e1cbd0c5
dd2d7834384d3109514c3856b694da1c129c72fa
17803 F20101118_AABWQK woo_k_Page_033.QC.jpg
ae920351cbac28e4464257aa70b8b3cc
b2b2f22021cb25b3f3c434abb978475ac5d0790e
4250 F20101118_AABWPW woo_k_Page_025thm.jpg
13fb1003485c916ea376534595b20a17
8df5b91d2ebf69290861bd36afda826ef3bb72ab
F20101118_AABVWZ woo_k_Page_006.tif
29ed1331b25fd63c4c6651577f6b1b88
bfae56f8419d4b2bbd659cc097a24997ba3a0a58
F20101118_AABVYC woo_k_Page_036.tif
982b3fda7ed6633cee66f9b755d2c778
de07ba76cafc8c7cd2f9fbdf8755167f73c37aaf
8009 F20101118_AABWRA woo_k_Page_041.QC.jpg
56c2e0cce0556a37f776a5a7ee06c483
83c017c98666f88d620ade680ee165cb821a6953
5445 F20101118_AABWQL woo_k_Page_033thm.jpg
975762fe2684867b53e665557e0d1dc6
3b2aecc46bf93a6c4903ed55002bde4c7a08abe2
15179 F20101118_AABWPX woo_k_Page_026.QC.jpg
9fafb76206cf453d3bebf908f90e7d19
e896a0cc9c3de7578b3fccdea4be5f4e46023639
F20101118_AABVXO woo_k_Page_022.tif
f2caa2a23f7964b20e3dd8a4963a54f2
f3c56abd24e18448eedb3e3aed4f3f14adf00fdc
F20101118_AABVYD woo_k_Page_037.tif
271f83b45af687eed9eb04ecf0f3b030
b1807a327a46fa329e6d349d0e0b23ea90cc3362
2608 F20101118_AABWRB woo_k_Page_041thm.jpg
36a51c4aa2ee0b964850b932b99ae02e
644348ba11846597dc4de02d868d366660874506
14961 F20101118_AABWQM woo_k_Page_034.QC.jpg
daf4fa675fc75062f9066f1b27d9f7f5
c5f12bfe80800d17eb3599786813d61aafe9b250
17574 F20101118_AABWPY woo_k_Page_027.QC.jpg
d8fad161ba4e38140701bd1fbf082205
c35cc0dd52acd05f584b4b1d6a60e1b9f110fe86
F20101118_AABVXP woo_k_Page_023.tif
b9042219395f96183641910c34429434
a0c08635b38103b423a764db171dec1392e37434
F20101118_AABVYE woo_k_Page_038.tif
9139e780f9289334f160580bfb8d9ac5
466bfff4c8ddb742bc270f04623fc0e516f35e3d
20852 F20101118_AABWRC woo_k_Page_042.QC.jpg
8eae896a29a60d29c2d83207a9ca2b18
c2b8c8da628cd824c8edcf401e5c49b51d4de776
4762 F20101118_AABWQN woo_k_Page_034thm.jpg
088fc843c5825c238b2e3aec62a59d0a
a2f9f8e207796129c26250be99a2d07294b0d134
5299 F20101118_AABWPZ woo_k_Page_027thm.jpg
ed6dc00ffb9c32cfca73a381b3ad79e0
97d34676ea26e82b755aa98ed009b53452f520f8
F20101118_AABVXQ woo_k_Page_024.tif
145b5a84368bf2e793f9510b63725a09
f5d366393ed26f76ccecb5f893ebdb936baab1b7
F20101118_AABVYF woo_k_Page_039.tif
4882179b2e27c17ca1fe7fa1222f720c
f37be2054464f2d961b6b0af182e89ba55ee5d54
5885 F20101118_AABWRD woo_k_Page_042thm.jpg
baf63a15f788f96a1d4d3f2c32644cf7
4dde02ac11cef7860459dcfb5efb9d84e189f8e1
17236 F20101118_AABWQO woo_k_Page_035.QC.jpg
13fb430405a7d72be2c6855ce7074143
232af74bbd8b6b137260a1ba079f500514c3c9f8
F20101118_AABVXR woo_k_Page_025.tif
94251175bc26b8dfbafff762b0c0906b
4502811bfe4ece65f92cd4c0c0173874a14aa2f5
F20101118_AABVYG woo_k_Page_040.tif
27ea78b04698d65a971d2b9b891ea43a
c6ac3ab0e870f7a83b38056eab1c689f10c83c68
16336 F20101118_AABWRE woo_k_Page_043.QC.jpg
46837aa6ebd42f0f7986b9b70f400132
5f388041e90705c2df012d4b035adab8bef3519a
4981 F20101118_AABWQP woo_k_Page_035thm.jpg
4b0bb6ce6a853e2af7643ff78505f43d
35620a9b8ca81e94a64736a16ff439aec0785ece
F20101118_AABVXS woo_k_Page_026.tif
983d37c558893ea8f990298a6201fbff
f1eb12882b1af342ade36d8abfc57de69839ae89
F20101118_AABVYH woo_k_Page_041.tif
b938d8d04a61c4fae41750fa7b070df8
a1c199068cee1ee8890ef3c0297b1843cfbbcb55
5080 F20101118_AABWRF woo_k_Page_043thm.jpg
b70bbe1fbb0276b51bb2d9f3390237de
a416679d4ef37a68be65ecf0d04b05f485754978
23798 F20101118_AABWQQ woo_k_Page_036.QC.jpg
bc60e93e73c3e1bfa935b5993e725f70
9d571a63cec57f4bac799f81cffd13e62d9eae24
F20101118_AABVXT woo_k_Page_027.tif
61ab97d08c3e96b16e70fa00ef5d5fff
d4a420289c93ea026ccf58ffcc57f24a8aed1dc6
F20101118_AABVYI woo_k_Page_042.tif
ec3918489971dcca9246c7095277211c
07174ebb5620e9a305ca6b0698fefca87b2ef06e
19046 F20101118_AABWRG woo_k_Page_044.QC.jpg
df0da2e468f2e23033bc11d9c40e7b98
e2ad818d267789b19d42c6a7b2f9ecdd01d4bc9b
6560 F20101118_AABWQR woo_k_Page_036thm.jpg
0b4f9d061190f36d39563474b2b0ca5e
5f2d80cb766471c0ecd85140a9a16814f6f66d48
F20101118_AABVXU woo_k_Page_028.tif
a3d9cbf5f52fcc4a579c545b4d224b2a
bd5733b9c137879856cb7dd857a6e9dafec63b45
F20101118_AABVYJ woo_k_Page_043.tif
ead453c1d9a921e31ba155e7bbcc345c
c518faa1a11ead413a9c23bf95ebf1dc1668371d
16667 F20101118_AABWQS woo_k_Page_037.QC.jpg
a99b0e10c502bf131125790985937019
733e68aed764b91c5a0e29af3af57306f51ea3cc
F20101118_AABVYK woo_k_Page_044.tif
fa349b58b8015996fbd157521399d66a
9005a552e915bc8540b84ba9283438faeeae0f48
F20101118_AABVXV woo_k_Page_029.tif
81b0228de33922b753d084687bba7a71
e4f9794b2dd4d156e7c3e80615c594057eff784a
5780 F20101118_AABWRH woo_k_Page_044thm.jpg
f953650634e2ae3005e8dc3bc42db873
d802345bde4fd0069a638d0b423340f263bdff94
5877 F20101118_AABWQT woo_k_Page_037thm.jpg
cfa8e7ad6ace68fa00607f5d21042eb9
0b81cf0b51ddf7db3dd88e6bfcf7618555bebe74
F20101118_AABVYL woo_k_Page_045.tif
6447bbd596bac0ca83d9598e5ab6e58e
aed3173ec9ae6059986a9e9e050bf5f55be0b556
F20101118_AABVXW woo_k_Page_030.tif
4fcde505f1107202ad96894cb7d0964a
ba8d7fa03f6e213588b082607a145a17ed28fc2f
18803 F20101118_AABWRI woo_k_Page_045.QC.jpg
2f9f3d2af1a86969f61a44009839db64
5f4e8a4ecf5e358de0e5870b16cf6bbc211b34fb
23924 F20101118_AABWQU woo_k_Page_038.QC.jpg
87bf5466efd184fa6ba1968db96a5121
aacd249fd0db5f627fcaa14c1c601525ef126dbd
F20101118_AABVZA woo_k_Page_062.tif
c24065f29a6bb272bcb3da1737dd9efb
08fe0047d8e52891681a84a9cb38706814791932
F20101118_AABVYM woo_k_Page_046.tif
fff677e55a08c8c3f217759a3412e283
4c130f7fff87290bc07d62126351b9b80a488c83
F20101118_AABVXX woo_k_Page_031.tif
d685e2d0e454593bed11051dfd151c66
0c14890bacfd70d55853acc02620ff7f8545669b
5544 F20101118_AABWRJ woo_k_Page_045thm.jpg
685d93359070b40ef8f6b93fba51367b
ef5428ab7281e0b91bb6ba74efa76baef71967e8
6595 F20101118_AABWQV woo_k_Page_038thm.jpg
327ba40dc3593fa66e9d70bbbdcb1cc6
ac20d250b8cb466befb3f2d0f32a5e4a151c73c4
F20101118_AABVZB woo_k_Page_063.tif
3de0c70e7be25ac79f0a89918caae540
df0bd86608b5445c3f1d663143e0ea514999e785
F20101118_AABVYN woo_k_Page_047.tif
5cd9a75c146482af22b62eb72fdcf01e
1d1b86a522c5fd27d0619a04162cf6821125d748
F20101118_AABVXY woo_k_Page_032.tif
a144223c753d305cda5299bdf261a9bf
dcf0d3518881096377c4d06d585240e2bbc8d8ee
17314 F20101118_AABWRK woo_k_Page_046.QC.jpg
20ca862ea3f0b7130f4598f9e003df27
24eeacb765bd00ce711eefa295ba5ccd393bbb0c
23644 F20101118_AABWQW woo_k_Page_039.QC.jpg
599ddfe87924398a7f50133c070e01d1
a9ddfd41cd45bba0a9e8c5192af8d7ba0c9dcff0
F20101118_AABVZC woo_k_Page_064.tif
e334cf6a0055aa16ca7e36906b835d7f
78e82441a5c8cce49d39f1204371074f05c6323e
F20101118_AABVYO woo_k_Page_048.tif
bd096c4199ef50612a771aa40db2fe51
25808ea180eb04b5031c287b9833265c55723c90
F20101118_AABVXZ woo_k_Page_033.tif
183e5d6d16139798e70ea0dc488b1e0e
37e6d130ed28567bd959e5efe3a0df32ff20ae7d
19277 F20101118_AABWSA woo_k_Page_054.QC.jpg
a546e0ddc46644335181d8fb67f8bc18
24768d674c351c50d3dfd165a5cf6951e8328e46
5196 F20101118_AABWRL woo_k_Page_046thm.jpg
75af1c80de93c74f72cfc5a82ca85459
ed2d7af820dacda9770da4ed6819c7baad77d14a
6551 F20101118_AABWQX woo_k_Page_039thm.jpg
207bd0a5da5c1ddf40395f80aaa529c5
fdd5cc4ece878a3de60cff2ae998fc8aea52d566
F20101118_AABVZD woo_k_Page_065.tif
7391f0bf0b80014591c5716e51336f7c
b04c78d682ff33c278b6adadc8961f075b08b33a
5621 F20101118_AABWSB woo_k_Page_054thm.jpg
8052ee05b96e0bc5acdd4fc92624f1fe
dfa9d1693bb90da82b71c786f36861d3a61c952b
16785 F20101118_AABWRM woo_k_Page_047.QC.jpg
0a2a1cf7aa5ac56b6aa088b78a4fe14d
c8bc153110768add4f3c7d7f777f2c6ced25e55b
12728 F20101118_AABWQY woo_k_Page_040.QC.jpg
eff0696fc35d1820208ee45332e01da5
0cfd1ee232afdc4602ab49e542ad78d2793ca9df
F20101118_AABVZE woo_k_Page_066.tif
5cb77e4d70b31404ae87fda9f18876d4
baee4e8d5eedfb8cffeda3058d5aa80f3dfd30d4
F20101118_AABVYP woo_k_Page_049.tif
9e178ac35309f2628c52e14d3b1c0065
ea6418f3dda28f2d62deae97a3ea99048a84d790
15578 F20101118_AABWSC woo_k_Page_055.QC.jpg
6d3cc70579476bf26cc31d528f0e985c
f1404307501bece62390aa18c4849dc9a949df60
5075 F20101118_AABWRN woo_k_Page_047thm.jpg
86148c2b98027b20c46810f4aaa4e6e8
e52f4344b743ca981df176c1ed4ec93cf9682979
4170 F20101118_AABWQZ woo_k_Page_040thm.jpg
ac9e3e55f648ea3313f6ae3a7b3f8263
d90abacf948bd58414cf96ad66d44be23ef20646
F20101118_AABVZF woo_k_Page_067.tif
56f0f3be1ccfa0e0d5d3cfc345342336
ec23f7f4badde045b7b86704ece2d1a9a8581709
F20101118_AABVYQ woo_k_Page_050.tif
58b039faeaf2505a2a526f5806fa97fa
fd7fd7cb6d222d65434065120be70a112b80bece
5669 F20101118_AABWSD woo_k_Page_055thm.jpg
36c0479a6877661c01413e37d720a1fc
2f33ce9938c25e2fb0dda1ee9a67c1fc23dc2a8a
19538 F20101118_AABWRO woo_k_Page_048.QC.jpg
653974a15272b7f0231e1276686c46a9
fb166416a03a733ed4eb30a5604fc0f5b1bc0168
F20101118_AABVZG woo_k_Page_068.tif
a18b50d9d546fd778706f34ed006fe0c
12de8b396de1fee0c60b16dc23294351f9679ac7
F20101118_AABVYR woo_k_Page_051.tif
f9c5f92e05f2a654337800ddde926634
4ff3049515703a34ac49829e79d69d876327a0b8
22734 F20101118_AABWSE woo_k_Page_056.QC.jpg
a3e67c5905727ef22a45d909a867f483
b1693cf53b98e201d49e85709060068f89d0c4d3
5494 F20101118_AABWRP woo_k_Page_048thm.jpg
f31f3cdfad920f25b15cd67435f14e02
4d2f853ef5f63de3cc6655e6b28ce22663a20587
F20101118_AABVZH woo_k_Page_069.tif
1ea9706a5f0ea1571aca54efc3d3c329
545294354083e7d19fba70778fde799a94e21db1
F20101118_AABVYS woo_k_Page_052.tif
6ea3748cf7c6c983a2fcb69728829423
d6bb51497c3a34daea88bf9839da9eebe6214a68
6555 F20101118_AABWSF woo_k_Page_056thm.jpg
77d2c60cc84868f887155e2dbd1fbbca
09413954a8ab8f5481d01562ddd9913764a93d27
11268 F20101118_AABWRQ woo_k_Page_049.QC.jpg
8ebab9cfbe3eb4fec0dbb904596be056
319176c30e3cd6288344711f7ab35f6aa5f97abe
F20101118_AABVZI woo_k_Page_070.tif
12ee2d661c10ebfb565652fd99f8dbf5
84a5e94cc08b905a818a177b8e488c430180ee87
F20101118_AABVYT woo_k_Page_053.tif
c122c5dcf9824215b49320ab80c05b8b
c13fa98ebee98d08ba96356b908bbcf26c8385cb
6193 F20101118_AABWSG woo_k_Page_057thm.jpg
45918fba04e514f41bd221024e43fc2f
3d9f0c474e735bba0ebc2cc3b73394f00eeea5d8
3791 F20101118_AABWRR woo_k_Page_049thm.jpg
a045602da3d223382f762a3130fbd93a
645cd5f037565c6e0374df89dd6fd952d18b1926
F20101118_AABVZJ woo_k_Page_071.tif
d949d6906f98fe8380de68a2d221c414
59d53b4fd21adab2a1c2ace4349118c481416b92
F20101118_AABVYU woo_k_Page_054.tif
c2418c6d08961b5919ad422b803586c0
bbfa43a53ec9feb0f663798e290998b2fce6522a
9438 F20101118_AABWSH woo_k_Page_058.QC.jpg
20713a96cdfef9f7dfbce6d69ca76bfd
19347d64df2de7773d536406a349bc28ff1eef1b
15108 F20101118_AABWRS woo_k_Page_050.QC.jpg
d63130eb6a8f0f06ace8a2bd0960bcc7
72d8265638f98bc4be25da376d63f28667a3730a
F20101118_AABVZK woo_k_Page_072.tif
ea48147d433bfac774222f5392f602e8
c00600dfe89b47dd7a318e5f8a48bf07376ae99f
F20101118_AABVYV woo_k_Page_055.tif
c2ab764fc0679e2ee0b8da451c5bf035
2d359005518eae059d75940bbc6e01769eff4f30
4813 F20101118_AABWRT woo_k_Page_050thm.jpg
f52962f6a9088956cd47c15162e79481
16428c55b61a833c039234e182be87e1cc1cc3ca
F20101118_AABVZL woo_k_Page_073.tif
326bb7d968dbe17872a1eb8cdb12efd3
ea77d809a73b6389e4b0eb0e79b29b3e50786c78
F20101118_AABVYW woo_k_Page_056.tif
dfa81e0e23850fd9b6511bea296e8539
444baa75bfd9b6256e60b859f56328a35724456e
2919 F20101118_AABWSI woo_k_Page_058thm.jpg
2251d3a1f6ef1a5226d02761d7b3d186
14cdbd42448140fa97f693773a0fa3d282dd1c2a
15936 F20101118_AABWRU woo_k_Page_051.QC.jpg
a857c6d9159b23c833ddf76e022bafe0
f7525d7f1e142a2cf58c8619a173e1ec22fb6c36
F20101118_AABVZM woo_k_Page_074.tif
2a1bad0a0193bbd86ca3031fff45f87e
93d8620a7bb7e38363c98814ad72e7e1bf12b4b4
F20101118_AABVYX woo_k_Page_057.tif
b7016346d823c7a9334fd20798b110bb
63c1a17cb143598afd65aa9457fdbb1d09225c02
21104 F20101118_AABWSJ woo_k_Page_059.QC.jpg
bd639bb7d511045ba0c004a46f98fe90
34b758fc8fc2e18a01bbf030e90f58cf33d7833e
4859 F20101118_AABWRV woo_k_Page_051thm.jpg
3081767de12aba831edf54e0830abbdd
ceb7ccefe6dd8114d32522f780035b1dd190ff73
F20101118_AABVZN woo_k_Page_075.tif
41de9bf4b4db2b8b2b40ddd354cc0d6a
db38ec2e290387faca8efb80a126e176eb5f4de4
F20101118_AABVYY woo_k_Page_058.tif
13fcbd166ebaf23353437febd0a9c2fa
da26f7be9d48f8839547d15634b6a07c74c69b40
5968 F20101118_AABWSK woo_k_Page_059thm.jpg
558d52dbcb092633750a3470e12673f3
9bfcc7d0a2d22b2214afb98ca68e70a3a4de4ec9
21221 F20101118_AABWRW woo_k_Page_052.QC.jpg
675d8f038e156d50fed74ca46ba4e85d
942080794733a1f9209a7de4ef4682fe1c2bf69f
F20101118_AABVZO woo_k_Page_076.tif
80b57f05dbeb1e3086e0dfd004ca6a65
29d57bc17b401f220e748aec61f31e59e42c7c01
F20101118_AABVYZ woo_k_Page_059.tif
a48a9a38c0d39ff3a4c355397d93ab5f
14c2f84829fcb6ea47915655c2ccba2284563878
5393 F20101118_AABWTA woo_k_Page_067thm.jpg
5c00cce379f8fc7cea0c0518e6874b53
8b145aa550448c3e7541477e9bda731e98be8e3d
17082 F20101118_AABWSL woo_k_Page_060.QC.jpg
64e670a38ff039cb9e8fa59549f6ecf7
385015c079e3853710c5373e463640246be2689a
6212 F20101118_AABWRX woo_k_Page_052thm.jpg
4ea8d2dd33291184bdec6330d6bfc204
77d2dc95281bd6cd24eff2ef0db844e94f509f29
F20101118_AABVZP woo_k_Page_077.tif
f197464a32e1333db4d9ae247f82db02
5da21ec32d365b9f446bee288b1cbffa78a77513
23124 F20101118_AABWTB woo_k_Page_068.QC.jpg
45c8f75731fd491bea84a4787a83aa66
4cc1a48c53bc6baacd6ae8ecf23774cd5020e113
4999 F20101118_AABWSM woo_k_Page_060thm.jpg
104d6543c799db31ed09e0e276954fa8
21072ae03750202235fa1d2a8c6883048efb08dc
8392 F20101118_AABWRY woo_k_Page_053.QC.jpg
cc5f3e3fcbfd0f6d07c02596e677f708
5225c94603bf9905cae6a961adee2344250cbd0d
F20101118_AABWTC woo_k_Page_068thm.jpg
d24e44f3726a4c8ede2ba299904c3dde
6c866bb64db380e52f580137470d10c891935c74
17928 F20101118_AABWSN woo_k_Page_061.QC.jpg
a058d81d94a7729eed791e379e5aa74f
1f3b1ebe8a2e0e60d2f3c5e98ea385066d29b9b8
2577 F20101118_AABWRZ woo_k_Page_053thm.jpg
7a52a692c7f788389c30a421abd835c9
dbe1a8f78198b597e4c0232f1433a12aa4dcf4be
F20101118_AABVZQ woo_k_Page_078.tif
cfac5d377ff17415ec11ebfbf9ed100b
5173045ac43d684edd5b6ac08eb9c91b9dbdced1
14154 F20101118_AABWTD woo_k_Page_069.QC.jpg
9f2753337646894b1f158edb0a07cda8
b6830941f0c01d49d19d27d39399f181fa217b0c
5429 F20101118_AABWSO woo_k_Page_061thm.jpg
94dc56b13a58dbfa0e2b10c4c32d7567
395ca99987e5d619228b6942967a3eb1ba00391e
F20101118_AABVZR woo_k_Page_079.tif
c3f4048279f8354c5de0ff4ea7fe8071
14b266f09a30f8f1985f017674037cbf228936ba
4400 F20101118_AABWTE woo_k_Page_069thm.jpg
f3b4e6fe25bc8db86ad506b7295a72ce
d8269f0a24cf79862269dea2420823d4d5f9e902
18568 F20101118_AABWSP woo_k_Page_062.QC.jpg
4268891f146ab318a929e1a2eac53ca9
b7e13fb8da6815a67d573145df296c56d765e2c1
F20101118_AABVZS woo_k_Page_080.tif
7d3b37c798f22080afba5a799ade63de
eaca5263ba00728a0cfd9d77f57f0df323648e3d
14274 F20101118_AABWTF woo_k_Page_070.QC.jpg
7844c83cd8a9ea4ecdcbe857e17c31d5
5ebfb62bb57b601167d174cfd8972c0979481494
5752 F20101118_AABWSQ woo_k_Page_062thm.jpg
4b5cbb8885dd7e0dcb0b1512756f94a0
433cce5be5d4192ac093c7faac16731cc6558aaf
F20101118_AABVZT woo_k_Page_081.tif
c494e4dbfc087742cf03619229ed9753
5aa6c3928f2ab4fbbe6de6353e51dfa63a8d11f4
4472 F20101118_AABWTG woo_k_Page_070thm.jpg
7da2f001703f4d88b4aca8f97b6aa0e3
818008fcdafd5d2ae633014a5e3c11099a08597c
23673 F20101118_AABWSR woo_k_Page_063.QC.jpg
c38145e59d2c75a950996509b4e2a999
1bb15805a597829e5069d106c5382edaced934af
F20101118_AABVZU woo_k_Page_082.tif
372f845515aaa24a3baa18e851817101
f82037dd576fd1790ec0cccc1144a24ee7beef01
21600 F20101118_AABWTH woo_k_Page_071.QC.jpg
1534be30b16c394c61ad71dc11b96e48
a28cf179baff361c0f91bc59811f03381147f13e
6543 F20101118_AABWSS woo_k_Page_063thm.jpg
7c3127cc7a9526014bebda5e931acc25
0b686b749df3ebcaa25ce8d592086aa1862378ca
F20101118_AABVZV woo_k_Page_083.tif
dc1ac7becf78f63cc3a3cd484bc8c3a7
30c22daeae80f6ae73741820c40f37a7c1f8d900
6126 F20101118_AABWTI woo_k_Page_071thm.jpg
8761bd9682a90345b8997fdff8130bbe
899b91d5d3b5d0aade099351f44f584bedd3be78
19372 F20101118_AABWST woo_k_Page_064.QC.jpg
5a29b9356641bff14872a1bb295aee71
053edb883e45fb7e3a373ba2c9f0c0fdf7ae1e67
F20101118_AABVZW woo_k_Page_084.tif
a2db57e82ab8f9c9ad8db431387a2dab
0a3d7d1b4c4a6a245ccf401fd4dd16e73f3c80fd
5674 F20101118_AABWSU woo_k_Page_064thm.jpg
1a9f8aaf2a924791ac8580679571d7a9
fda4ee8a36bbb6e0bb9aadf4fb5566d8b29605d5
F20101118_AABVZX woo_k_Page_086.tif
8090a8571b986be97cdd4c3997d231b3
16787ed79cc83d8b23759ffac9fc23ee0ffeea47
17599 F20101118_AABWTJ woo_k_Page_072.QC.jpg
31c3c4c427d00809bc360a3ba6d7727b
4a294eb17b26774238864bf2335693517e50d53f
22811 F20101118_AABWSV woo_k_Page_065.QC.jpg
f0c2718519f5a1b5554971a84993e9b5
c43b5f8660cb20b4b03204c11ab94647478231da
F20101118_AABVZY woo_k_Page_087.tif
f4b5da5a2f7ada17b1d4b6c99d01d38f
4a275f5f04b501fb1f0977d5f4edd500500974b0
5163 F20101118_AABWTK woo_k_Page_072thm.jpg
e87a91c70e61225de2e76cc72428ef1b
ce6ace4608951ead184ce79f963456c810084d12
6425 F20101118_AABWSW woo_k_Page_065thm.jpg
82f45bf7f156fac6eda08d778a81012c
fe1040f201b3faa798beeeaa45136feca759dece
F20101118_AABVZZ woo_k_Page_088.tif
f066f9cdf74946ef9de1906b2354afc3
dbe3d95a82bf2b8a2d62db201f51ed3e7ff0a14f
18772 F20101118_AABWUA woo_k_Page_081.QC.jpg
90a7a3cfa48d47494c6a76a59b267c7f
ececf16adf880ca2b0b2904f4e5ae84139c205a6
18010 F20101118_AABWTL woo_k_Page_073.QC.jpg
d784fc974ccc19949a0ff5234062e873
f83007e17c99896dd443c67fc26e033340051f80
13992 F20101118_AABWSX woo_k_Page_066.QC.jpg
bf32753e5b88c284bfb02ff7c1125d44
88f5932e644aeed1b644a996356abad50462c8c8
5392 F20101118_AABWUB woo_k_Page_081thm.jpg
5529badd3639962b2e136e6f9dc94fc7
64e4eac3ed52176609dd0c3c9c0f82b88b7c89be
5454 F20101118_AABWTM woo_k_Page_073thm.jpg
278aba15a03147b128e45526691de3ad
298b089dc1942800642ea564f36c9a8736d3355f
4538 F20101118_AABWSY woo_k_Page_066thm.jpg
3c4d40caeb8690d54a9f3ee5e26937bb
e56963ed627f05f1449e16825c8a78c488c6272c
20149 F20101118_AABWUC woo_k_Page_082.QC.jpg
1c86fe4d3753ca3feb872f83cb6ec178
96b449e2a30770d6f6cd4701a061366c392a4cbe
16905 F20101118_AABWTN woo_k_Page_074.QC.jpg
40b8a2898cd74a525e36a2389d8c40a2
5919fe863d7f510531cbfa8baff1456eb198e2dd
18064 F20101118_AABWSZ woo_k_Page_067.QC.jpg
f9ab05ae977f01a25a3af670afc4ebda
9fb0774ad3ba767016d683bd884615c42716571e
6010 F20101118_AABWUD woo_k_Page_082thm.jpg
ba12871eb09e19165f78c20e4fc7558e
f294d8f78096b7af06b9cd71d2ed36d89c0b4ce7
F20101118_AABWTO woo_k_Page_074thm.jpg
75efb7ee221d24132871676e1e41b35b
878eec3432f2473e362ccc552303b80e828e6c59
18280 F20101118_AABWUE woo_k_Page_083.QC.jpg
d5fb370ce4544825719f1f7e71fd8aff
eddbe95b6b3bfaf10e06d72b3cf7102dc1b5942f
20774 F20101118_AABWTP woo_k_Page_075.QC.jpg
d7dc1b25307b3992fa6db94eee918f43
5c817843c9140f1c49934eabab1213098a068d01
5475 F20101118_AABWUF woo_k_Page_083thm.jpg
d775dc13fc910c397cf59fce5539f76f
1b553eb584d3415f565cd5f1e4a914715a3507d0
5906 F20101118_AABWTQ woo_k_Page_075thm.jpg
e1bc5e9cee9ee8aaeaac3f352f139b63
eb28c933ceb84d55f3782e6ad1924875257c57f8
21048 F20101118_AABWUG woo_k_Page_084.QC.jpg
03ec45a92fd9a91044720304ea2ff5fe
fadffd94f7d6be43b7f9cc627a7c0c437ccf6938
23056 F20101118_AABWTR woo_k_Page_076.QC.jpg
c32946f938f31fbb0ccd8fd393708a85
2691e89bdff7c7b2a666a21179d7ee584f2c4bf0
6054 F20101118_AABWUH woo_k_Page_084thm.jpg
955d1221ba0c0a64bc352d475b468e70
b5ba8db16d943b0c67c2ca580eb156bb3924babf
6350 F20101118_AABWTS woo_k_Page_076thm.jpg
17ee2bb50f0c98c40c428f26e832156b
f9f40347471f7b5d4275d605638864c53236c84f
20899 F20101118_AABWUI woo_k_Page_085.QC.jpg
7d39019d71abecfd9f75010d0e715d8e
bf9f1e8bc4f9dfdd8f8fcb5b21615433699f4239
22974 F20101118_AABWTT woo_k_Page_077.QC.jpg
cac44975f2c7a0c82fe9285e8630ff5b
108c39679a3b3dd6b840f08c91432e3fe886c5c2
F20101118_AABWUJ woo_k_Page_085thm.jpg
3de88af4f37608d8885174fe0e2b4fb0
4a2654b82261d8d27e1ed4b5315e48ad825ad51a
6577 F20101118_AABWTU woo_k_Page_077thm.jpg
b4c89d9419f94e83f49fe1efe861237d
0a25312ef6c8101a851668ee30db166f93846ae2
12844 F20101118_AABWTV woo_k_Page_078.QC.jpg
28c63ccb64d80be31a36bc2436175013
17e15787bbb2d1cf8051e236c3250e380b034762
17991 F20101118_AABWUK woo_k_Page_086.QC.jpg
5841c676cc68d2fc379e1663255675ae
eb6502b8bcbbeb7abe80fcfd811391365111dba4
4267 F20101118_AABWTW woo_k_Page_078thm.jpg
fb4b87eb025b09d3837d2b13d8bea6b6
ea452d365b1c1f0fbc902fb599ad035b743eec72
21671 F20101118_AABWVA woo_k_Page_094.QC.jpg
2f0f45ccef6b68823e5803ae6e1fd702
8255e4bd2bbdd29f26bee17d4d2452dd2e5f88c4
5291 F20101118_AABWUL woo_k_Page_086thm.jpg
282c4ddd809e7158971ec32e06763d23
30ae60296b4764dc56499837b66b0078e17e7865
4214 F20101118_AABWTX woo_k_Page_079thm.jpg
21c8d8d6264cb9315b696c06fab818b5
ad26bc9c9ef050866933848dd24d18810302f259
6467 F20101118_AABWVB woo_k_Page_094thm.jpg
5134edd8fd782a628c0cf77f9efd4fee
497779aa9e7e559840de03c0124ac6c917d9ad4e
17564 F20101118_AABWUM woo_k_Page_087.QC.jpg
247857e64e083a64dc1210b5f90f5155
82e696ee128094c16429f1a37e6150cef755fff5
7912 F20101118_AABWTY woo_k_Page_080.QC.jpg
663ab84e9ebc27a4df7ddff664d49db2
f749b5b32ef8f919ef0dc805d3ba08c56535eec2
20134 F20101118_AABWVC woo_k_Page_095.QC.jpg
a004b86bf1e808e364da6f90f509618c
df75b0a5477e9e8355417c80bfc5c41b94d364d9
5259 F20101118_AABWUN woo_k_Page_087thm.jpg
602742e3de1aacedd1af7b2836e46914
02bb7f284b7f1ffe965a0c83587ce7a098b8afd2
2505 F20101118_AABWTZ woo_k_Page_080thm.jpg
6a97f3199d46d352e69203eaa3b08f44
7ca36ce0a7cca544827c4f9f482e35aa9147c2e0
5975 F20101118_AABWVD woo_k_Page_095thm.jpg
f0815c6b2945694956659f67c0f24b80
7ae915f4e60bbc6ae0750dc306264c409bd1ad79
14931 F20101118_AABWUO woo_k_Page_088.QC.jpg
ce4a57cd2f238cc53cb6baa8e69a7f8d
3b47b5747f5fb8af5ee6dab38f4fffa42b3e6cdb
6541 F20101118_AABWVE woo_k_Page_096thm.jpg
5b0ca4e5bf66c382553deee474bfa41e
d39fe85e1ee4846ec89879aef4170d4f6c730503
4636 F20101118_AABWUP woo_k_Page_088thm.jpg
2e5e5b7c70378910b6ffc9d3c807212c
a57dbe965b36a840e5a91841f8db959b66b5d462
22611 F20101118_AABWVF woo_k_Page_097.QC.jpg
9a6e33ac71f59bdc59f9b152eb7006af
c885be698f71a4fa24db27b4f73c5ce18165184a
14117 F20101118_AABWUQ woo_k_Page_089.QC.jpg
4d3673f105bbd6f0c7403120bb8730ef
6434caad4cf16e006898c47f5262f26bc49e86d9
6449 F20101118_AABWVG woo_k_Page_097thm.jpg
4afd1e220da2631adcb9bb101bb93964
247ce583c062aeadcd7afc8472994e209b187653
4642 F20101118_AABWUR woo_k_Page_089thm.jpg
b9c7d34b93e1ce8818a51c9b316d05ff
76ab851155025893c5e432a4c05644e07a6146a5
24472 F20101118_AABWVH woo_k_Page_098.QC.jpg
b319fbb72bdb91363d248946a1aa5993
e52acc1351160e458d0a136236f222cdedc023df
13107 F20101118_AABWUS woo_k_Page_090.QC.jpg
c1fd7c5a08cf54642f7153ddb4e6c843
bead415e0d820206ec9ceae08a2914874fce2f17
6774 F20101118_AABWVI woo_k_Page_098thm.jpg
534d4d68486194f39360f33eaedf7579
eae57fe2f60dd17442d75a2130d390965eedaa47
4086 F20101118_AABWUT woo_k_Page_090thm.jpg
1caf502515c191a8cd52dde123c5d91e
3375b34240f849af9790b58000707234f1aa0673
22993 F20101118_AABWVJ woo_k_Page_099.QC.jpg
7701a9202e75ec86c2d10d306c7255e5
243298a9b062c4048e2c42a90b7b87b09912e681
13440 F20101118_AABWUU woo_k_Page_091.QC.jpg
384de42ac9766663406efb8a93f32d7e
edecfcd96b1ce38e4aef9888328964b52331b6fe
6531 F20101118_AABWVK woo_k_Page_099thm.jpg
50190ca7118b38ff8062a0a4f6f4b570
dd8cdcb4be5c4410f36c12af412750facb70f0a7
4083 F20101118_AABWUV woo_k_Page_091thm.jpg
1f5088528d4f199d71322027c7c412d0
be2ce0cf1a782ee325d194b9082a7c6db75291a7
14256 F20101118_AABWUW woo_k_Page_092.QC.jpg
b7860e6222f785256797e0eaefa6e77d
fc3328d7df68da7607145afbe36e297c4b76e6ca
2205 F20101118_AABWWA woo_k_Page_107thm.jpg
0d701c596b8d72a06b284786cd723ebc
956ef1ffd479b7ee1fe6eaa08e84034ae324e602
22266 F20101118_AABWVL woo_k_Page_100.QC.jpg
b641cc05958b963bc2c23458629aa620
7bf6eb32d918060d5ebb9b5e09f05ea2f945b99b
4480 F20101118_AABWUX woo_k_Page_092thm.jpg
2a48131c50e1c806cf7db515c0facca7
50debbd556b0594d68d5edf60efd604c6b3115c6
8619 F20101118_AABWWB woo_k_Page_108.QC.jpg
6d9abd5d0c78909c8371a0ad1e63d52d
8adb6b878c4ca03cfbc5afec49a16ccccd3545e7
6437 F20101118_AABWVM woo_k_Page_100thm.jpg
f7f46991becb7a4b8e926b032662697a
29b392a466daa7cd0ea7f8b28b7767179e06e506
15413 F20101118_AABWUY woo_k_Page_093.QC.jpg
3c21097360b7303f4c9c99cc0a8bd9ff
d9af6271498f4961fda872c724c2ace3b1514555
2737 F20101118_AABWWC woo_k_Page_108thm.jpg
f7025ddeb72fc1f45d08a4d767c730eb
5f34a3019eccec584feb5d9cf2479e137522d090
8855 F20101118_AABWVN woo_k_Page_101.QC.jpg
56b1edc40e2dc9c6e946ec07e80ffee1
c5de52cf04fdf6e94f0efdba9aa55c3052808f91
4947 F20101118_AABWUZ woo_k_Page_093thm.jpg
d5d3dfde4f48a3b3964a8e9ff2784a6a
17cd97ea03ec6f101e63f459b1c5a42a69532bb0
7347 F20101118_AABWWD woo_k_Page_109.QC.jpg
6697206cf684a1ad3488fed00f0877ef
48ccf71fa1f9733e36da32f44d96ab9862c9fa9a
2749 F20101118_AABWVO woo_k_Page_101thm.jpg
cbb480f76509f635e8c55a96d03c8b09
d092a9daef1512ddfe2215bb5ad9a46f58687ef0
2488 F20101118_AABWWE woo_k_Page_109thm.jpg
772cc07431eb432f86330bce3a8e70f4
c88b3050e7a258faf68043868c54897291d86203
11988 F20101118_AABWVP woo_k_Page_102.QC.jpg
db5afcae0ad47944a5e52f4f889dd9f1
ecd825162ebf95b6e38b28344d28e51da3c51dd9
7104 F20101118_AABWWF woo_k_Page_110.QC.jpg
160e7d7d2f1c2248f4be44cfeb8d3549
9b6c59de54cb0889ac000cef2d54e3c9a94c8d31
3888 F20101118_AABWVQ woo_k_Page_102thm.jpg
294ff4aea4f513c2ed203b8713edefd7
a0cd296372181a5c0ac5164525c95f551b222498
2461 F20101118_AABWWG woo_k_Page_110thm.jpg
e8db4bf4752370d6f8594e5342eecb45
f546efa8b84b65f4ba9ab25c26ad79676a5b4e7b
11932 F20101118_AABWVR woo_k_Page_103.QC.jpg
0705bc78d3bada458ad9e4b88d5b51cf
280487fe55b0b28e1727e4d72e118aa150cc7db5
8060 F20101118_AABWWH woo_k_Page_111.QC.jpg
127397e0d73e1928a4f939f30e98e915
dfe7cc973635af5c78b0bf50a9a511e70a8dfa36
4003 F20101118_AABWVS woo_k_Page_103thm.jpg
3dda2bb414fdb94034c4e3e003156fc1
c520b621c353cd8fcbc933b3175a65454e7aceef
2710 F20101118_AABWWI woo_k_Page_111thm.jpg
9ec926436444cafdbda09dcbdcc7d0f5
645eb86bf344634d022b66c70c5f1eb2e051a484
20115 F20101118_AABWVT woo_k_Page_104.QC.jpg
79c728485c95201d3cbf763b157ec865
6d099abff207249acb84edc50aa51d198249b210
F20101118_AABWWJ woo_k_Page_112.QC.jpg
d30b06e651394589742fea1c53cb0c7d
8d51082b0f24cd5dce979cd6b64bc633d1802de1
5937 F20101118_AABWVU woo_k_Page_104thm.jpg
9fadde8a314618dd63d24db3f2ad0073
393ac302ba2f958b1e8c88ed7c6f6bc744d0ba54
2331 F20101118_AABWWK woo_k_Page_112thm.jpg
9616b663d2821b9bfb88126df5c843b3
79755a1f80e00845e96fac9cf9b147e5ff1144bb
23339 F20101118_AABWVV woo_k_Page_105.QC.jpg
ee0cb55b2b34fb0f20db1326f0bff8ac
17fda1fe9b07d2a293897cf6280f7fee211bc50d
6554 F20101118_AABWWL woo_k_Page_113.QC.jpg
a5037086923ce1f41539c43f01ed92c6
dbc340b4145fa796f721ddc72a4d45f2e6bd7609
6472 F20101118_AABWVW woo_k_Page_105thm.jpg
b3d0d6308b082a36d83352f1896710c2
a29e74f3e5d0aeec92f860c4ba76723aa6a0e1bf
18945 F20101118_AABWXA woo_k_Page_121.QC.jpg
99dbff014e17c7f5526b5f98836e9071
da422973c78378057a3b73fcc468b67d740e4cd2
21987 F20101118_AABWVX woo_k_Page_106.QC.jpg
f5e2b99344a8f8de6f7c2fbd31ca8408
36aeb01517f1c6bec21b10c83dea6f2cc195e03b
5969 F20101118_AABWXB woo_k_Page_121thm.jpg
77271ec81f0571c5a1fea2b5eae16ee8
b41ad0419d5e6bd4d984813d70ca968daccfde44
2355 F20101118_AABWWM woo_k_Page_113thm.jpg
dccbfa7ecef5d1379c28167cec7b1625
95ca0151c6d48e3b99771453edca8ef26d1011f7
6300 F20101118_AABWVY woo_k_Page_106thm.jpg
a42edfe9dade4765ce845d6ca82c1223
4909132269798091fedda096e5eb8c27ebe342d8
10859 F20101118_AABWXC woo_k_Page_122.QC.jpg
625dd387058642f15a4f2b9f4709a410
6dde801a5c964c35d4174044ca3986394cf0a4c0
6775 F20101118_AABWWN woo_k_Page_114.QC.jpg
a233d9ad34a64bff57dd9f7501652cc2
64607b676b35d31a354befca2d00278850a363bc
6154 F20101118_AABWVZ woo_k_Page_107.QC.jpg
bf377eea3200c6b5b12c2a06e8717f09
435c193ebb7abe5c048f148d070a3c00e8f65ec5
3696 F20101118_AABWXD woo_k_Page_122thm.jpg
759abeda5ba293fde4239670d5ff4af0
94a9b5eb2f8345c178cfc1ed89fb1bcd806aac2d
2388 F20101118_AABWWO woo_k_Page_114thm.jpg
c47588ebb1cc1a0c1ed6eb50c480d5c8
2b67cbc7fbaa80d8f4f3544e3587f458a0013958
6816 F20101118_AABWXE woo_k_Page_123.QC.jpg
f2d649a9bad1e31560eb0358cf7edc46
93545460a169e78dcf971981880928926d01b724
6568 F20101118_AABWWP woo_k_Page_115.QC.jpg
921ee95f4b373ee243f33c180a352efe
3e14b2707420e7ac8f595d45539a8c4a6211700d
2368 F20101118_AABWXF woo_k_Page_123thm.jpg
39da65ec175a1314bf58d06ba7fcce27
786989478c970179aea74f2a048036d4669a67b0
2361 F20101118_AABWWQ woo_k_Page_115thm.jpg
fb38dd8e0ace23cdf817aa3bec251a2f
38dd5a21562c9514bfb2bb2c0ceb997fd078625b
19616 F20101118_AABWXG woo_k_Page_124.QC.jpg
f8fe444641f4ba426ed16d293b9aa27d
baa25d2024ba1c5a32cceabecf7c7ec33d1cd1e2
2394 F20101118_AABWWR woo_k_Page_116thm.jpg
f8b3f5f13c97756f0a748797201ece19
985455ebe29ec05d09db188023b524d4058a2afb
6188 F20101118_AABWXH woo_k_Page_124thm.jpg
856fb62b95a5cd85440e4992b87a229d
1b2a96b98e17964e644c0edf8ab3933aec290bcc
7581 F20101118_AABWWS woo_k_Page_117.QC.jpg
c3ea9d13f3fefc3ea74ed7a98cb561b2
ffdf0a75e667b8520039e74da2e1b35004cde6d8
6634 F20101118_AABWXI woo_k_Page_125.QC.jpg
e1c4b00e1b1ae540cb5c70abe408c1b5
d5c0d2b7a9d73a943b6eec22e79b3152cc76bff2
2524 F20101118_AABWWT woo_k_Page_117thm.jpg
392c0d894c66fd9994f9c9d04b264faf
186d9cf3959a17d64ee18b24118b32289d3fa6ff
2432 F20101118_AABWXJ woo_k_Page_125thm.jpg
3e14c280eb0a4232f992460acbf85564
80a06b91eb59fe6305412ec936af356ed71f2997
7671 F20101118_AABWWU woo_k_Page_118.QC.jpg
c5408b1170836a87db25209d6a14caf3
088f1bd2292f07c562c572899470176485582297
6129 F20101118_AABWXK woo_k_Page_126thm.jpg
91bf0c70efc00557be2be4791bb3108f
8d1b226f90689863700a54b8492ed89504634101
2522 F20101118_AABWWV woo_k_Page_118thm.jpg
5574437d030f0433d6513d73c1960eb6
934fba33fdab26626f6fba7dec8fa482776a07b3
6773 F20101118_AABWXL woo_k_Page_127.QC.jpg
9f477b9248be5b7b6ce423ded208cbae
39c66ef9a15107ace7950f4427310fc9f4aa8615
8008 F20101118_AABWWW woo_k_Page_119.QC.jpg
dc87765a2ec0807b3e6259eafa6ed9df
7160cbda6b8d5e42ae82da1af8fa577183cb5faa
6702 F20101118_AABWYA woo_k_Page_134thm.jpg
201980eef9b6305e5e50ecabfe3159b7
8bf7ab9eed2047a5f844da40224d7a7f2cdccdbc
2378 F20101118_AABWXM woo_k_Page_127thm.jpg
7c135983ed9d579c9f8bdf2869c8f59a
0077b323b7160168baa4f8901614d623d4117356
2686 F20101118_AABWWX woo_k_Page_119thm.jpg
918799624981e385d499065564f4fabc
0fce7fec324e04268f4189066d13c104164d7b16
2616 F20101118_AABWYB woo_k_Page_135thm.jpg
eb37bf5a49bdb6e2d25399b4bb659627
c5c44411514d92d90df4d0172812198b0c51e209
8214 F20101118_AABWWY woo_k_Page_120.QC.jpg
d954936c68c2e72f20c0a48c8fc13f58
b8a5a1382669f3bec64363ad608aaeff111b4cdb
6284 F20101118_AABWYC woo_k_Page_136thm.jpg
d115de55f93b7f3d48d03fd19a9e56ac
be8b865293f326f921dd94bc49b84075cf1534cb
21873 F20101118_AABWXN woo_k_Page_128.QC.jpg
405c62e770c290a746c7173203b7c3dd
bf74acc478ee4e1d3ba7db0475fb5319413de4a9
2661 F20101118_AABWWZ woo_k_Page_120thm.jpg
207cfbe2d4c80382dce6f426d2b70255
b165940c875817292384cdaaad3d6e5956d8ce71
21268 F20101118_AABWYD woo_k_Page_137.QC.jpg
ee57f1795b27f1100718a5633abe5648
e67b79e8a0651b0064d313e7ed3eff9ad1a416a5
6632 F20101118_AABWXO woo_k_Page_128thm.jpg
c7cf60823656765bb199338e63856c8d
5065e9984a65b5b829b0a01be7218831e155abc2
6327 F20101118_AABWYE woo_k_Page_137thm.jpg
e810ba4c7b7276087bc184423f84042d
2a6ffa97cda7723cbce30411da2c59652cdc19bf
6325 F20101118_AABWXP woo_k_Page_129.QC.jpg
0ca4e39f9a603fbc46ac611255f06a2b
dbbee414a46767a9c1f9ccf3a6e1485ea9c13fb9
21486 F20101118_AABWYF woo_k_Page_138.QC.jpg
5ad0e6fb22d2708cf1bb4681ec1b2e4a
a9e8ca259372375c24ae1bbc9fdda82f9b71bfb3
2239 F20101118_AABWXQ woo_k_Page_129thm.jpg
4d35e116e429d14ef4afdae970c2aac5
7b6d6fcacbaa21d34472809fe513bbb446d3d399
6353 F20101118_AABWYG woo_k_Page_138thm.jpg
69caf79c3a3c02f3a0524e7b7421bee5
b8b2b56b70edc9411f699355b9752b7cca78ec93
19680 F20101118_AABWXR woo_k_Page_130.QC.jpg
3c5236bfeba231d9816ca5fd493bc378
00540da22d30078c2cb612e1e65415583ce01005
2498 F20101118_AABWYH woo_k_Page_139thm.jpg
92080e9c7109ff9a436144858b2b5293
b840975979d28644a37905f4fb8da64ec6600ea8
6183 F20101118_AABWXS woo_k_Page_130thm.jpg
53d7545ce8c955810786437bd8d4bc83
5adadcdfbc35a31917e1bf1ca88c96b05c7460ed
20964 F20101118_AABWYI woo_k_Page_140.QC.jpg
d3b3a62b33f10da9fdcabbbb1bbf95fd
2c7972ec542d2bcddfb3f78e9e65c90836d17124
6512 F20101118_AABWXT woo_k_Page_131.QC.jpg
d364b5b67464307494de302c8c163fdc
e3e5b44885c938bcf1e444d0a654ad13b39fe0e8
6453 F20101118_AABWYJ woo_k_Page_140thm.jpg
da128ecf39b799b941a34199110aa42e
8e6124cb8111ca41ba91f5ec1b38fcd7a916ad89
2321 F20101118_AABWXU woo_k_Page_131thm.jpg
d175ace82128d46e656226c9325d6bcb
92e0bf46977b602c98136cbd4ddcd244371fcea4
21515 F20101118_AABWYK woo_k_Page_141.QC.jpg
188adf7c7449c6cd3fe9baca1f2af264
2125b37294410ae969bec66368fecaeac3812a1e
19576 F20101118_AABWXV woo_k_Page_132.QC.jpg
5262b26bb7bfa001a9aabe8605efcd05
4f7d6a177878f640f99aeaebf06dc62331e2fc5e
6426 F20101118_AABWYL woo_k_Page_141thm.jpg
39f6f9cd0f3bcdbd6d8eab124977eb61
2f0e993ddd1376717bca9e7cd9d8bfbc386d7f63
6163 F20101118_AABWXW woo_k_Page_132thm.jpg
7a3902a4f25dec6861b963debe06c389
391f2ee7b60b07c353763927119af3aa3d02576e
10290 F20101118_AABWZA woo_k_Page_149.QC.jpg
169dba6e38a084b6e52e5c06893c87b0
6a99bc71846234951fc1251594d2485bac72f1e1
12535 F20101118_AABWYM woo_k_Page_142.QC.jpg
bbefd7d50107bb0cbc01cd4b0475e704
c74e30bf3304406460be18574c6b737043ebc465
7255 F20101118_AABWXX woo_k_Page_133.QC.jpg
4a34d5b6052bc029e4181c599848dba0
d71fe50d46461a5b18b3758c7bc1e04a49743c81
3368 F20101118_AABWZB woo_k_Page_149thm.jpg
52c242a24fc9772fd9e48f7385edb6a5
09ecbdcd42ef243bc863dd75bf6977c43b2b98c0
3947 F20101118_AABWYN woo_k_Page_142thm.jpg
19744b05573ae5aad2de30f1b21495de
8037ea724028fd5338ac2cc96154f7c8d12aa17c
2467 F20101118_AABWXY woo_k_Page_133thm.jpg
cae8e99431e78847f9026accb66c69d3
0e4fab054cbdcc6d5ee4f07e4bfee726bac526ed
7244 F20101118_AABWZC woo_k_Page_150.QC.jpg
65f025b2f80c27de96a35978b8f85e97
8978c0049c477fd4b33648e52fd1872b3cf35668
21321 F20101118_AABWXZ woo_k_Page_134.QC.jpg
ce243567e25905327eed3e5afb2be59f
64e14e67e23014f8afe0ee3c066cbf0704034a00
2606 F20101118_AABWZD woo_k_Page_150thm.jpg
cbebfa314121d025e375de204c10da9e
14f9430018451bef7ae03bb2cfd68ab3c9407cb1
7461 F20101118_AABWYO woo_k_Page_143.QC.jpg
ed0dd1bd9b8539c14a7e7f32df3b2038
766a18ac49ff8c94ff4d697925459ba4275c839a
7435 F20101118_AABWZE woo_k_Page_151.QC.jpg
af0b3497329d608df8ef9525bd3e2cfc
8061ab7d01bbe85266fec80ade493b67ec048fa3
2564 F20101118_AABWYP woo_k_Page_143thm.jpg
fc1c5665d98041a5d19bc99c3e7864c6
8d130e60f18f57d7170ce9ec4806eee7a67af376
2611 F20101118_AABWZF woo_k_Page_151thm.jpg
2c126a75ffc2dff96958975af95d7968
d33374eb3e2343ca9f365bf3da35dc8d07c9b97a
21684 F20101118_AABWYQ woo_k_Page_144.QC.jpg
8021f364a1e87d0606d63aa295496d6c
fcdbf7523fe3f15a7a9f6feea41cabba5ad48eb7
63982 F20101118_AABVJA woo_k_Page_008.pro
c5953d0d70335348c145c13dcb346e75
72de5403c66fa252616f7f9042c9d1aca0257cc3
7276 F20101118_AABWZG woo_k_Page_152.QC.jpg
1a26ea4ba1337a6f7544bee5a7f30556
479b2f0826f63bef0436a430242571a35402789c
6435 F20101118_AABWYR woo_k_Page_144thm.jpg
d6b90cbeef7230719876447e8e76b273
d1373f52bada6247674d3e937c0f9c26fd8e7d23
873974 F20101118_AABVJB woo_k_Page_064.jp2
c015e82c85f1a28759927ca7090f8327
04c159ee9c5c42afaa27222c3c71b9379c0cb0ec
2585 F20101118_AABWZH woo_k_Page_152thm.jpg
32858c49dbb7846b30e43805e025a693
9b31d968b80d123a3e89748036bfd69872d6d87a
21379 F20101118_AABWYS woo_k_Page_145.QC.jpg
49ae11e488ae38887a48f5575c83c821
0557801db202a3f29b3766e479e77fc0acfb8629
808 F20101118_AABVJC woo_k_Page_037.txt
4046ccdf709210d1b3ec91b21abc49b8
e0010d8074388cd5f7a061ee9f4be554d5fb85bd
7457 F20101118_AABWZI woo_k_Page_153.QC.jpg
244712028b106842445c38c45f835428
73a6e652e23034a039d999fd987094d4da2d473e
6317 F20101118_AABWYT woo_k_Page_145thm.jpg
d521ffc55744b4ab576648637229fdf9
758195e8631170c038ac45ecc43ae805ee6290c5
F20101118_AABWCA woo_k_Page_141.tif
828d93b56313f52f80b14cab3d032cbf
85ca679b8242d8143f4fc28600e5134d92c0bb09
875434 F20101118_AABVJD woo_k_Page_086.jp2
8cea68eef441cb87e39ab1cb5057b85d
2f69e2d2f5a192391d11336943a009a6288db62b
2523 F20101118_AABWZJ woo_k_Page_153thm.jpg
12d866f2c96264098b07a68ce0d5b235
9925bc9e5cd3c83c3eaaa53752f9ab0f9a7de8a1
7071 F20101118_AABWYU woo_k_Page_146.QC.jpg
3aebdda18ad728941fa8bbccddd3e91b
407377d9ff2cc5517cb93e146528d30722d2b700
2141 F20101118_AABVJE woo_k_Page_128.txt
cb32ee33be562bb1bf2eb2c754cc92fb
25acf53efb33ac2fcbe58686fbb31e4872cdd1fb
F20101118_AABWCB woo_k_Page_142.tif
153f654ccc704851daab640728291248
ff6e7da8b391aa4eb778eed8c0b94a7d41caab62
7928 F20101118_AABWZK woo_k_Page_154.QC.jpg
4dec58a4ec524ca646559dc349c4dbea
81efaf4310cd7a3f880d32ff253d0ddece2abefe
2347 F20101118_AABWYV woo_k_Page_146thm.jpg
f02990d99a295df9bdb33dd8419c57a5
205f8091335285eaf679436c60bc9ef06244be7b
622956 F20101118_AABVJF woo_k_Page_043.jp2
46b5d6be454ee12bfa62f0db08c42121
df8d55e66d6ee7e125de4711b678c823bcc731b1
F20101118_AABWCC woo_k_Page_143.tif
de50ff927ae79a3649e979bd5d679eb3
630c5cb0868ea69f7fa20ec4240e0758483cbaf0
2595 F20101118_AABWZL woo_k_Page_154thm.jpg
453624d39a378da9644d8c908596bbad
b5ef85409f2f507dc927438497ca675a47d9b4ca
20919 F20101118_AABWYW woo_k_Page_147.QC.jpg
210a0ef005dc03aae47ad762676b1f43
7b92064da57f323788033fe78c55225adce5bcab
916 F20101118_AABVJG woo_k_Page_159.txt
7eeb87d28aa85d690c76486fc135539e
ddff0a5f231efe9b78df7bf6637fe1bc96858448
F20101118_AABWCD woo_k_Page_144.tif
dc0e220a2ab4fdc625e90e617e1f17b0
8001c05265f559b716ded79c9ea3789c448436c2
18634 F20101118_AABWZM woo_k_Page_155.QC.jpg
099fdff37fecc5304e2d48e49db31a5e
86c028c2898810a6d7b7107e76a3771a2ddda6d6
6396 F20101118_AABWYX woo_k_Page_147thm.jpg
d98aeae352583b1dcd3cec23fda8778e
2a24252674aa51e95473174b6f332bca810d2bcb
F20101118_AABVJH woo_k_Page_005.jp2
421a0bfdcaec22eaf4a80e76a8b9e474
82269085281e402529439a450a63c7547af86e64
F20101118_AABWCE woo_k_Page_145.tif
af9ff7dd0bafb1ebebcddec6f5a70a94
f35930782657f81df35c55d1d473583b836a8f9a
5427 F20101118_AABWZN woo_k_Page_155thm.jpg
79dc35bd3d5132e6c9951c5f620f5bfb
d1e8dd188a1b101b918c15cd0e872492b3cb9883
7094 F20101118_AABWYY woo_k_Page_148.QC.jpg
91ce72635a99bf6aa34f2b72a35f5d69
2fd7b608b3d17a253bed397920fd3c0ada4379ce
23883 F20101118_AABVJI woo_k_Page_096.QC.jpg
25a1c8735eb3e524d9b49d9c1d095341
ea56a48de516094ddaa519caad02f1770fc1584f
F20101118_AABWCF woo_k_Page_146.tif
e5a4e44ac16428335d7db2b332f8633b
8830e2907ace487a2da4a16fb5200339f639771b
22698 F20101118_AABWZO woo_k_Page_156.QC.jpg
c9755dd916eaf070302042421b1594a7
f4e84d44e8ea75aaf66b59d2311907241b5916d7
2484 F20101118_AABWYZ woo_k_Page_148thm.jpg
8ace60dd30f1c0ee6a300bcd4f5e4a96
1b4ac5167e272176767cb1e4d67ae2375fa6fc9a
4741 F20101118_AABVJJ woo_k_Page_026thm.jpg
07b7e1b9306f6b078e0e6db7cc246fc7
c0ab905e1e870e4488707b3c64f6dd0d2598b39e
F20101118_AABWCG woo_k_Page_148.tif
4b3b6962d12a94bc67a2447186e0c2b8
cd8579903cd8c9ebc7689a173fb9555ed442579e
21530 F20101118_AABVJK woo_k_Page_057.QC.jpg
4fc0cca2b10728067a37ab2b4bb4ab2c
16e35bd645170afb766009fee3936b259d9394b7
F20101118_AABWCH woo_k_Page_149.tif
7e8a9596d1b68c0162b9b8df71389436
6c66c1a65fa83bfede8cbba6491289589473c7dc
6605 F20101118_AABWZP woo_k_Page_156thm.jpg
aff7df4a88acba6de9af0c1ce6514246
09cbea7d8c777c786c383d4cac852a44d8c9ae6b
F20101118_AABVIX woo_k_Page_013.tif
968dc457594f110af88202e09e9f6fe1
0e5d5d15ab468d7504aff4e55d3a79c2a5006962
43497 F20101118_AABVKA woo_k_Page_136.pro
cce8856d7dda9adc46cb934e9918f7da
4ab03b7aa9a0164d642d2d3c64d7452b2066df0e
90600 F20101118_AABVJL woo_k_Page_085.jp2
17cc45a6adf7399636dd8cf8dc5f08cb
815e2bcf4dc5d8b16dbcc7c6927d1b03f0e19c3a
F20101118_AABWCI woo_k_Page_150.tif
434f80cf9fe819670dfed86b6cb2fceb
f8a64272f970b0a087ec34e63aec88f424a60d21
22987 F20101118_AABWZQ woo_k_Page_157.QC.jpg
6edcc275bbd48936f5566305b1548578
fdb630649f0d3976a288c87fe0815ba57beda2fe
45959 F20101118_AABVIY woo_k_Page_137.pro
224317d0b21ba84e84943abb06d8dc22
9b540ab2371ded71e506152dbe4af4196e865d1e
1984 F20101118_AABVJM woo_k_Page_094.txt
fd9b4aa86e65018a12267e6c050e6704
b1b738df678e3e01b71ea4a5bf38fdce557cf39f
F20101118_AABWCJ woo_k_Page_151.tif
effdd28caf01bf1c628f22cc8bc5df27
745978b00fb02e80558a8dbc323cdb7e7e8a7453
6422 F20101118_AABWZR woo_k_Page_157thm.jpg
7fab234aeb00b08ba477dabfad7e34cb
a266a6b4d78a85b67146f9de78422f4b3734f3a4
7867 F20101118_AABVIZ woo_k_Page_001.pro
bdfb99c39c169db9216ba229843dea22
34f686d500bdcbcca4ddb8089b71057754e12344
37586 F20101118_AABVKB woo_k_Page_132.pro
37163ab1ff78a7dd600afcf2d4d151eb
a96ef2c110c3e89a1d28c3262467311a3cfd2ca0
52134 F20101118_AABVJN woo_k_Page_016.jp2
58158045f9edda7f85effe70bd17ba34
ed800969a543a23dcf616fc871785193e594cc79
F20101118_AABWCK woo_k_Page_152.tif
8d1b71261b253cc19f2e493a6be62e28
fadf718adbc228f223bd66ea3461badb1b3fb891
10803 F20101118_AABWZS woo_k_Page_158.QC.jpg
99972fbb5341717cf15577c36bfaa5fe
fdae70ca6fa633eb93d445c83072db8921b129f3
69760 F20101118_AABVKC woo_k_Page_132.jpg
2dc9e673c089de86d2b402a4e790cc86
f50e4d148c8c36beb65836c7a9bda611cc3d638c
F20101118_AABVJO woo_k_Page_057.jp2
2bf15691fb8801d81554c409c6cd9c7e
97dcb4666710291662d8b70b6e15b7e8c596c811
F20101118_AABWCL woo_k_Page_153.tif
f9173d2c1279eb6265998ff4cd3f74df
fbf0a184b065cffefcf3fbf50c9f011715422468
3418 F20101118_AABWZT woo_k_Page_158thm.jpg
1d7b7a972078f6cc895d617625516ac7
0be195b45f862e6b98801689ad1accdc673d554c
1932 F20101118_AABVKD woo_k_Page_018.txt
f882fb22052b6f31318deb90d137c253
ed9c19645a98de2dc33e1f074bdc8fa29008e677
39186 F20101118_AABWDA woo_k_Page_012.pro
f6da987daa4dee9459986e1d4794b598
3934e14933edf93f57ad38880c1cbacbeb11f9ba
F20101118_AABVJP woo_k_Page_147.tif
ccbb19ebfb27ad32c62a07be2ebe122c
449f9dfa9945a363b11ead98658573fd20cfd3e4
F20101118_AABWCM woo_k_Page_154.tif
4f10cb9e1fa9c31fb0a6870bfb699122
6aff83a49fd2a66b45b3c95bf87bc114f34a7fe2
12514 F20101118_AABWZU woo_k_Page_159.QC.jpg
74d170c930c099f5383b15fcb763f7bd
766ac9b356222ecb3e507d43e6bb37a7e2cee2e9
7958 F20101118_AABVKE woo_k_Page_135.QC.jpg
fb31a1d736b40d83989f7146cd6a5990
8f31043e71ea159b4336b0138f6f161ee50c0a41
16795 F20101118_AABWDB woo_k_Page_013.pro
cddc7a483e6f4e5a079111c4c899e87d
8fefee05b88b428ad1b7d76da2459f04b17e4553
6752 F20101118_AABVJQ woo_k_Page_116.QC.jpg
616d3a3cdac2b0a278be5ff71c7f124b
302ee093acf7ef10d310f9486b4780aad82c2e54
F20101118_AABWCN woo_k_Page_155.tif
b5a5cf581e456235710377ff5c86649e
2ca3fe07072a5e42a70065941d7032df97553d90
3716 F20101118_AABWZV woo_k_Page_159thm.jpg
bed5c61deb18114b9f9c9b1c7bb69615
452bd13c64e17d4b3a9081f8ef2f43f460b8f7f4
37207 F20101118_AABVKF woo_k_Page_058.jp2
9759b5fb7146c7c68378caa9065e54b7
ce6e0843f99942bab730147ce24ab54054870d4d
44864 F20101118_AABWDC woo_k_Page_014.pro
8e8b2f22379c42039fd196d7e2df42ee
fa394b42057a672369a6b91a2572eab67cd0d67e
32378 F20101118_AABVJR woo_k_Page_083.pro
2617dc3370ec7c86127c8197b7088cfa
57dc839fd18d4a0fd53d9ffeb2272b9392b49313
F20101118_AABWCO woo_k_Page_156.tif
518c3e79ae237ed4e3954c0e304cc047
2b34970ad347486568cf14618cafa82a04b82eef
180871 F20101118_AABWZW UFE0015340_00001.mets FULL
3aa57afc14a4c129a6eca8c8c1e07ae5
a23366680d204b39b93a11cb495b2c652d250f12
F20101118_AABVKG woo_k_Page_061.tif
38287a1d6e13d95adc715baa079c2f16
6a2d244d4aa72cd2987157e0acee73a86809270d
48354 F20101118_AABWDD woo_k_Page_015.pro
5c5c18645d4fe0fa9ef34a5faac521c3
48a29e9265b611f1d18b1c4f119ac400068fc0bd
36912 F20101118_AABVJS woo_k_Page_102.jpg
5b530fdd18aacdc20d2b0869db3106d9
8107d6405676384253b242ca198b7df30d57d4f8
F20101118_AABWCP woo_k_Page_157.tif
3c347376b48a12f2051ada2d140aa107
d220986cce9f99d4a1fa5bcdd39cf34a8a62fd8b
52853 F20101118_AABVKH woo_k_Page_098.pro
36d3e39d5b8d133cbcced2882423b923
bd0e0aa7624141d7565e932e8e4af718e5e47241
22899 F20101118_AABWDE woo_k_Page_016.pro
19e9a3ce91a0122e93b70fd48dcfa42a
e443677118684dfa302d678f98f46cb9a7d201c8
F20101118_AABVJT woo_k_Page_085.tif
b6b25020c2fb3fcf6afef18d7474fee5
14b8ba69ea37791c787b7ed9a93d2f164c35b4a1
F20101118_AABWCQ woo_k_Page_158.tif
42c50718ea9208567b3ee85bbc0505bf
662dc77c86c086ba58e4e920534ce6db591e1ae7
15884 F20101118_AABVKI woo_k_Page_003.QC.jpg
37d509ae39a597c9a0769e5a1ba83a6e
c90bece2065bd3b31fb7ffc4682c67bdad40baa4
43807 F20101118_AABWDF woo_k_Page_017.pro
578b9cdcc1174dca8a1e9ad11ca3659f
257693d6d94cba5edf2e2f31eda33b30b0a4d824
2070 F20101118_AABVJU woo_k_Page_098.txt
8d2317fb085c39be2712cdfb970b582a
a66da4d209e80e6003cd6e7238009bf9c4fbc9f9
F20101118_AABWCR woo_k_Page_159.tif
8caa6c0043e68de17fd9c953ceade245
e4770685ef8e5efb0eac49d35ca6790678843209
48493 F20101118_AABVKJ woo_k_Page_018.pro
b375264c346a00a42be93d44ac58d339
e73ba2a1a46777d02a409f40d77c7fd70dceb127
36337 F20101118_AABWDG woo_k_Page_019.pro
f5b0127946efabc67efec05e1b974b3e
11587dd2120aeffd336ccf275f92fcdee6f3ecec
17729 F20101118_AABVJV woo_k_Page_025.pro
9d3cfe07829e9952b5bd728becdd2126
b1b768c0a41ee30edfaaf11832ee10036882bd8c
1094 F20101118_AABWCS woo_k_Page_002.pro
683ec0b40e0461c9dfd955e40e6d08cb
380fb5d4d93721ca9cae09093abd66687089260d
1026047 F20101118_AABVKK woo_k_Page_122.jp2
1159063da56a21b216ba02e5475835dd
4acbb86175bd9f52bd9303c4a84b7722128f10ad
47855 F20101118_AABWDH woo_k_Page_020.pro
3f72c419d160b14bdff13603f53c0085
3c1f2aa842f9c639e5788440d707d8e470f428f6
278692 F20101118_AABVJW woo_k_Page_125.jp2
ed086c1c77f3cad5dd9ee76c479419c5
b778c0563365e02fe16a26b0412642cc6881e04f
31689 F20101118_AABWCT woo_k_Page_003.pro
d313fba3f059699e636b3f3a7a6f1b5b
7fafa800590c5496a35a99a19e00c6efc3d97f42
233995 F20101118_AABVLA UFE0015340_00001.xml
5bcf368476f70360a2ef92e46b92c761
a1a84a8b755018a3d71590902132f2014c76c121
19815 F20101118_AABVKL woo_k_Page_126.QC.jpg
857606b3b909003679e166c1daafb35f
6cbf84186c31ae0d270d69a2695ff21a8b3f4af3
40096 F20101118_AABWDI woo_k_Page_021.pro
ec87885314f4290e6d2c333b68b9a1a9
738f7940192ac22062e8a0fef071366644ca59fa
1786 F20101118_AABVJX woo_k_Page_045.txt
f050f865de1f8d734ec6068ae0a5b582
404b9a279a984d2669712b2d20c1c8700bcc1822
72033 F20101118_AABWCU woo_k_Page_004.pro
264c8e055f5852ce9ea09c070b018a34
248b2fae55400a29cb1cdcaa57dfc168fcbe0b70
2010 F20101118_AABVKM woo_k_Page_020.txt
7ffacdb1c8ed20910fb4e5fe8be3a7e2
e9251eabb52c4e26cc0bb2604b46f8d7ed489b89
28788 F20101118_AABWDJ woo_k_Page_022.pro
417df6f4ede149cd7330f57ec0ca2620
d2d468018427db031bef0d96031efd3b8449464a
21317 F20101118_AABVJY woo_k_Page_136.QC.jpg
bb319470a31f2c3449d543471a6d46d2
ce1d667312b103d68853e3a6d9c9daf9788dc74c
96002 F20101118_AABWCV woo_k_Page_005.pro
fe1186bf435b0e529d2346e56b3d7283
27db32aa6d891c46a798a457abed8050aa37da6e
5961 F20101118_AABVKN woo_k_Page_116.pro
4264cd3a57bfb5250ee7297c5ca8ff11
ac1fe84fb6203c264fffe6685bfc69bce2ad9a5c
27796 F20101118_AABWDK woo_k_Page_023.pro
994fc4f67c9e3e158753525b1cbcf3d2
eb05f2ad3c6a88c0da156a0d6a6ea63742caf951
70859 F20101118_AABVJZ woo_k_Page_003.jp2
a923afc48994d0c4ed0b7f49df0d8a1b
4b158f585c5757eafa7ad606f605f05c47db841c
18519 F20101118_AABWCW woo_k_Page_007.pro
4e05cee25fcb4381700e9108528ad6c9
58d648cbce34a13a3d824c39cf8eaf14b141bbd3
F20101118_AABVKO woo_k_Page_060.tif
977a2174954533a89e711e715d9a94f3
497a61f0937e1646f202ba99d27871c9bd597faa
30889 F20101118_AABWDL woo_k_Page_024.pro
5e78e0851cb4c14772d0a84408aa9ee3
1a55d50ef1ac3990170c86e799583cd01597e5bd
74261 F20101118_AABWCX woo_k_Page_009.pro
108b33c5d777cd9e8195c7df5bd932a6
e942250036c0924010fad6d3b9eeafb8e2725a7b
17051 F20101118_AABWEA woo_k_Page_040.pro
1cb3fd10d5d959f52c83f9d3734e43ea
4f0e1e6d4f1be735edb2a46b7c9b64e5c48704a7
6237 F20101118_AABVKP woo_k_Page_020thm.jpg
9ad131e3889fbd76b0a4a8b147792a6b
ab4883d0c70af4870f73bcd941f959985b39cf91
26268 F20101118_AABWDM woo_k_Page_026.pro
90e9fbee61fe2daade634bc712d462ca
222e3fc5feacb5a37ae01f4e6f9aeb4a1288030e
22942 F20101118_AABVLD woo_k_Page_001.jpg
78f9c8ced45101a201a5ed7122bb4c68
79a9ad27d4d68aab573f583ca30b83f1531c5c53
6693 F20101118_AABWEB woo_k_Page_041.pro
64eb1bde2500ae95755184b64bc974eb
654c08be53bcff67d66221b6c1059a7587d9917b
8490 F20101118_AABVKQ woo_k_Page_007.QC.jpg
760aafa3d63dac673187bee050b37adb
7d9eb71adabacf64cb86e2d2f0ae89e19a28ac7f
39361 F20101118_AABWDN woo_k_Page_027.pro
4b703f8818abc327bdef7ab5d7b0aa5e
cb909907c5841ef886131187515a8ccf824d86bd
77683 F20101118_AABWCY woo_k_Page_010.pro
769766c7014d31da89d2b0a464735ca0
f1429eff2fcb01cc8b1796650da3436af8e069cd
10263 F20101118_AABVLE woo_k_Page_002.jpg
2d99f041f0420b361df7f815fa4f3812
3238dba3ead5ae6a2ac319ae0b312203527902a1
42743 F20101118_AABWEC woo_k_Page_042.pro
a5a83325141403b8291a510f77606621
98dc6ddf43ba856bbcc0b8e330a463a4fefb35d7
1055 F20101118_AABVKR woo_k_Page_088.txt
4e74d174cd7e5f04522602101270712e
21da3de78cad936860bfc13d840fc847f43861b6
25418 F20101118_AABWDO woo_k_Page_028.pro
8a03a46938a133ec7a83ee7eae62fd4f
0c9ec45fbcb2fc36e55b44a3fa2679d5d6b66167
8512 F20101118_AABWCZ woo_k_Page_011.pro
c5d55f026487b710e7326aacae5dfd8c
5d511a23f6ddb9c11ef444dee4f810180475f99b
49253 F20101118_AABVLF woo_k_Page_003.jpg
6c9f731b6e7798b6d2aecbef7e79ad44
2ab20108c4387ac4572a71e0cda8bb5ec09d1386
11624 F20101118_AABWED woo_k_Page_043.pro
8485071b9e4de1b0bb07f507ddd2eb4d
cf8e3d69afc99fc85b920a4c8ea69b37a37bf8a3
22874 F20101118_AABVKS woo_k_Page_018.QC.jpg
eff9afa3b8126fb20dfa3368e0da5940
8751774ccfcead3247626c81cc9249418bb2fce4
42651 F20101118_AABWDP woo_k_Page_029.pro
7bdce1b401d10bdebb493e81465ce1b4
bfb28bdafafb4e92198653326882dc85f0e88bbb
72828 F20101118_AABVLG woo_k_Page_004.jpg
f9c63c0caacd01de80d5649f13884bd7
8a7796b20b9b5cdf4383b339845a93cd00542a48
35904 F20101118_AABWEE woo_k_Page_044.pro
e6f8cedc60b7d38a627785b184d5fc65
9e42009755a059bf04639659c6f52ebe8f9c0081
7452 F20101118_AABVKT woo_k_Page_139.QC.jpg
c16e1a57ecb89dad7d024211079892b7
23093ea1e5d025ba020015a73fa2da2eb3e11b6d
47301 F20101118_AABWDQ woo_k_Page_030.pro
e346686f7251c8a1916f37442156260e
e6c95f6bb576715613b1b91d23ac74b40374df1d
98724 F20101118_AABVLH woo_k_Page_005.jpg
bc938f4250efdc013bdd2235fa2cd460
0dadf1b3f2ba693717143cddbff3d8a9ade19ddd
41213 F20101118_AABWEF woo_k_Page_045.pro
5706556d91243b1d1132f7fd887eafdd
e25cf59a5a9a6d20518b66c7ce839a2c73770948
12774 F20101118_AABVKU woo_k_Page_006.pro
4b2d4a1fe4443f7f4dd188d426d80b7e
93ab3298f66d28c234bc772ee20ec048d43f5551
14146 F20101118_AABWDR woo_k_Page_031.pro
30e89d85dafeb52f2e0421a2de962ff1
1024c0c22f2702d2509362a255b447c372ece64d
23353 F20101118_AABVLI woo_k_Page_006.jpg
d69bb098881a7411e8be3b28b7b597f5
68e6a5f1357e2da6ab84994908e38c7c51a046f3
30741 F20101118_AABWEG woo_k_Page_046.pro
52dd9290a68d9f3574d0f50b6e4ac4d4
5b087b7e91a35b4a19897dc10e8d4a1d743c7bef
13638 F20101118_AABVKV woo_k_Page_079.QC.jpg
ea80f4fbec67fc46367c6967a8c85419
8e578bccdff4cd1ba86a03fc2b888e2f643454af
43276 F20101118_AABWDS woo_k_Page_032.pro
be8e23a4844a9860c1eabc70e39e30ef
396d15589df0b44a3a6a7e7d7302254ffe226c3c
28778 F20101118_AABVLJ woo_k_Page_007.jpg
632cea10244e253f38b8604ec8a14831
17bec0708a3853877f3a862ea47d9db9e6c621a8
30936 F20101118_AABWEH woo_k_Page_047.pro
7eec01ad693d0aa272dd7e50e8efc4dd
37a6d9b0463ee0b25c2e494bd7d26351fb8d7637
18861 F20101118_AABVKW woo_k_Page_012.QC.jpg
600c8160a8d2bfc912fdfb76cd97cfec
dca58f8c72ba4592cc529e41b83f0abda7fb8b7e
36712 F20101118_AABWDT woo_k_Page_033.pro
25912e0501becb673a8981f9a48b1a7a
dfcd2017deec5c7605589841c1364f3b242de65a
84626 F20101118_AABVLK woo_k_Page_008.jpg
9a6c6ebbfe6616015dbb53add6938fdd
236521cff52e2e7572873c82402a5243d08deec1
41455 F20101118_AABWEI woo_k_Page_048.pro
c6e1bf6a7dee20dcbefb467e5dd1de5f
57b7ffb4ca9ccd9265016391eb9f75919f52ebfa
74796 F20101118_AABVKX woo_k_Page_140.jpg
5cd746b46712df9007241a5abaa56ebf
ae24dc68c8e1f86517c245bfa0d898e553b67eb7
22515 F20101118_AABWDU woo_k_Page_034.pro
a46aab11ff00739f70e3b7890a741c3b
42332861fe21e422a632800cab8d2fc57c874098
41188 F20101118_AABVMA woo_k_Page_024.jpg
ad9b0383a45490a8bb4c9f7e27121d7e
88c0d634fb4a5bf4382ab2513717a8a415a9f4ed
93894 F20101118_AABVLL woo_k_Page_009.jpg
61a31539363b211ef9b5cb0397c3b427
0c4e99337d7bf49e1c6d8a5626cecf98a9da4ef0
20508 F20101118_AABWEJ woo_k_Page_049.pro
35d73b90980f9ee9500a3b24ec2792e6
6a7ae710d227a65bfff6f3595efdcfc45fe48a75
F20101118_AABVKY woo_k_Page_140.jp2
d618905b83cd96de12aff4a24114509e
ccca36d0a58f28f611090dec667c29ca0fd7f324
29871 F20101118_AABWDV woo_k_Page_035.pro
fa43162afa4184093062222182c728fe
411b7b702738790cff488f523fffbaa37a0c1664
40883 F20101118_AABVMB woo_k_Page_025.jpg
e2ca68ce75480fa4e726a7103e09811d
c5b577381bd735065c9be445366d8e7a7f77d894
105258 F20101118_AABVLM woo_k_Page_010.jpg
556a239cf9dcaeca3dc7fc413efd0bb4
bb05b5b6e1311c43b1d4dd9b91030b4de02d0aa2
32521 F20101118_AABWEK woo_k_Page_050.pro
2c70d9548875efa54d15d2356b5b6cbf
2cf6cea412319366b143e5db70b5d9fd5ac0ac5f
6770 F20101118_AABVKZ woo_k_Page_006.QC.jpg
36fd510afc2fb0f3a65f6f406d27cf3c
24a5ea14aa87bac83fc938abc467776c17403643
50842 F20101118_AABWDW woo_k_Page_036.pro
7e94c1e86d78334090602035a1c1b2de
bba8825ae16850a39ab4d1333bdf0cf6e3d0fc49
48416 F20101118_AABVMC woo_k_Page_026.jpg
8bdf14eed0a4a30afac70c533cce6173
1291f3e7d9242297dc20492d7999cd6a6ccda8b7
17951 F20101118_AABVLN woo_k_Page_011.jpg
6c236da2e26cda634babeb0b2c0d4751
77e2c57e7f05084a20934b1d92ab109ac2dc4f70
34893 F20101118_AABWEL woo_k_Page_051.pro
4a7e5cdc09a02d46230b151ed5cf3cf8
0e978f887ea4f63289e9b18a99c2ce367d43a68f
16604 F20101118_AABWDX woo_k_Page_037.pro
0faabd6d5df013c68b40fab6ad83359c
bca2c7f06caf5523e7c1edbad1d45ed6d5450b84
59334 F20101118_AABVLO woo_k_Page_012.jpg
e48ae214b83e676f7447fb0d6c286952
9320fa76a718e6a0e92822ba671860caeb9ead03
35809 F20101118_AABWEM woo_k_Page_052.pro
b1311322ba81bc368ed63e5e80bdead1
59af82b472c1334d30fb77dc41417b374735662f
52924 F20101118_AABWDY woo_k_Page_038.pro
1cff095d9652a8148838907c85d8b740
d40baea461c467fc20fb695f5d23052dda668cb3
55357 F20101118_AABVMD woo_k_Page_027.jpg
7a7fcfbf21fa9e5b02569c5801c7dab7
cc76e3bd2caff62bb10bb1946a801da0ec545f1b
9879 F20101118_AABWFA woo_k_Page_066.pro
ab77f76301edd6771fbafa389e87973f
f78f54976fd5515bd5ea7fca05e975ee21475a6e
29339 F20101118_AABVLP woo_k_Page_013.jpg
2029290f6aa972d61b50b9420c28df25
3b1b8b94df3cf20de8ad44c3c3a6153b4a10784c
13133 F20101118_AABWEN woo_k_Page_053.pro
65784d2651dff10091a98271e1cdcf72
17700434e612dd4d3fceb37d9a556fd05c8ea787
49241 F20101118_AABVME woo_k_Page_028.jpg
9995e7421ddc2c5c2f488c2302d6dcde
2c51a2e7e86a5be2f0aae7f78964e8a41fda4321
33148 F20101118_AABWFB woo_k_Page_067.pro
fad08679003161716cef8dee9e9c2f37
0375a5729729a7f3d719527abcd05095a2b9ff6f
F20101118_AABVLQ woo_k_Page_014.jpg
b59a3743986800b396b2f1248c3dd1df
91e7f0ab40fe3d647e4c58524477bbdef8e357a1
39579 F20101118_AABWEO woo_k_Page_054.pro
536d892c646879d16dab8016b842f24b
ec1103a933432a2e9aa8f3c9198fe5c2ea77b2c0
51912 F20101118_AABWDZ woo_k_Page_039.pro
2376c736c520c1e1becec833524557c5
41f2a9ef3a0e97a6137e29090706c409f9297431
59945 F20101118_AABVMF woo_k_Page_029.jpg
f0db123d8bff9a7c5657e80108082391
2ed95c71641afa9a0b1eddbd624ea2789df01bfe
50376 F20101118_AABWFC woo_k_Page_068.pro
b0ec60c7541f10ccd50c80a71f68226c
7973817e2027577b78e012529d90be8ece1ab059
68862 F20101118_AABVLR woo_k_Page_015.jpg
8135b3cfa59e9f5b5a8dc9a044f155cd
20c73d8b03fe6e1336cc2ad19b6ddfd9bedb0a84
20842 F20101118_AABWEP woo_k_Page_055.pro
6e9ed6a3a3157814d6a7b360b71805b3
aec1366af429b52bbc1b6a89ba8189e0b5994290
67991 F20101118_AABVMG woo_k_Page_030.jpg
d1abbb4be4ed0cab03c74c362cf4b2db
a3d8670db3e91de0d9acc958e391cee4bade5b44
21126 F20101118_AABWFD woo_k_Page_069.pro
94d8f53e0d350de595eb093c5db266b6
ed39b83d2fd403e314e536cf43591f9236343ef8
37951 F20101118_AABVLS woo_k_Page_016.jpg
199a4410d4806adec9d63072d1982d9f
e0d7fda0120512efc1009efa9e3b3099d29efdb5
48066 F20101118_AABWEQ woo_k_Page_056.pro
7080af3a5321213d9e4cc85f1b58b423
b1b57d5f2aa175b1fc967a5d0db8b562593d664d
47486 F20101118_AABVMH woo_k_Page_031.jpg
d12f267ac7cfbddf20a6064e2e42df2c
82c615e7764ccd767422abc6619c9826d3f5681a
18360 F20101118_AABWFE woo_k_Page_070.pro
8df90ae566d478c1089501ff91be9437
b856d360677f3648a7b2be017dadd5ff594b6769
64833 F20101118_AABVLT woo_k_Page_017.jpg
8a75553a22d088532cf67860ce7f6cc5
555863e2cce8942d8b576ac512ba46c44c48e82c
30634 F20101118_AABWER woo_k_Page_057.pro
2464c2de92947378f5db4ddb33996062
7deec061f9457f0ac45928c801f3690a0ffc1e18
61718 F20101118_AABVMI woo_k_Page_032.jpg
43c792b7255276ca06e103cdb0e17543
c225a7368e5ee5138ba49b4c96bf7481d5c3e5ce
45411 F20101118_AABWFF woo_k_Page_071.pro
861348d1738e5e632ff29fed8216d6b7
9a97ec7ecef9a606f37fbb887e6425a5875159bd
69555 F20101118_AABVLU woo_k_Page_018.jpg
5940cc22d8af342ce4fe4e1eed4101e1
619ec4d9cc1759f052f5e5b37329d1e57b62c751
15883 F20101118_AABWES woo_k_Page_058.pro
cacb7b7588a89865e7eba53a693c8c9f
0305ff6e5ef174555951c13cd95ea59ff2ebbfb9
56366 F20101118_AABVMJ woo_k_Page_033.jpg
64f7f2e7e7c4c1adf48ff472a134b510
d54e02742f00d2a8ea378f71e8a22ec518cfc421
25042 F20101118_AABWFG woo_k_Page_072.pro
fec8acf6e300847d37f60ae2b62f8664
06774767b030f0b82b85237a7ae38cd7fc125927
51184 F20101118_AABVLV woo_k_Page_019.jpg
edaafdfc7a8ed4363cb249796df3b698
ee66a2e20f93d72ee492d91e40b53c694cdb95f4
45297 F20101118_AABWET woo_k_Page_059.pro
efe5a56121a21c22ba970b30d7ebfb37
a7ced8cdb229ea424a1690b7c46d9110f78c3de5
44631 F20101118_AABVMK woo_k_Page_034.jpg
e178a2356359d61e57efb1c2e61bea87
31639154af9e46509cb285b54e427c0c558caf25
23970 F20101118_AABWFH woo_k_Page_073.pro
749baee2b9020fb99c3486e311beed77
066db5ee64a95b413ab4c5f543ea2e0af80a81d8
66726 F20101118_AABVLW woo_k_Page_020.jpg
0da4e50fbee5285385df20963800f4fb
599ee85b804df300bcdefe8ed364647a1d837848
24386 F20101118_AABWEU woo_k_Page_060.pro
0d1bdfbe369770bc40e67e2edb152dc2
5e79ea76620bffe8032faaa9f442546474567494
46106 F20101118_AABVNA woo_k_Page_050.jpg
bb466d640dd41141baf046083668ff6c
15afa091a951a5bc4634e4d591a8e24c5ae4b553
53086 F20101118_AABVML woo_k_Page_035.jpg
0461e2c12f14fc64060143736b86aad9
6e1664edb416380e68aea3234cbeaf0cf5dcbd28
29088 F20101118_AABWFI woo_k_Page_074.pro
7bbb2cf8b49cd6fdb3c9f0bbe847e022
74e32da86c3f1144f9561c2f09e538b8669d716d
52055 F20101118_AABVLX woo_k_Page_021.jpg
b1e8b520a980b5540f8058045c0d0f29
ff2b06204944078ddd4951afdf0612fa9b2b41e9
28242 F20101118_AABWEV woo_k_Page_061.pro
ffad13c7dffbb3bcf57cc0cf411245f0
24af23d1342e9ac8893b15779b1c3bfbb5875f2b
46961 F20101118_AABVNB woo_k_Page_051.jpg
2a5f9c36ed1e86c5f7172876d58e4a77
be8733ddb5e9e48e6cf0b96d4cb9850d62e505c5
71298 F20101118_AABVMM woo_k_Page_036.jpg
c766dbd765dcbb160353334fdf9cd2a4
51270175abc10d10617b1cdb881e29eca09e5086
28477 F20101118_AABWFJ woo_k_Page_075.pro
2a1bbd348b6cec72341d7c8197b815fb
84f9d7b25444cf7218f3b088cb893d2063693c34
39242 F20101118_AABVLY woo_k_Page_022.jpg
75e92dcfdf912aaeb44e3099cf343d12
16480047a623bf905809e130635b611c374298f0
26131 F20101118_AABWEW woo_k_Page_062.pro
0f0e7997fbd6e1a2e3b2c831ed4fe42c
bd27adcabce93ae006145beda449d40c387c9eb5
68383 F20101118_AABVNC woo_k_Page_052.jpg
d3236a49b72f3b38a454c6c3bb20f5f8
2217351b4cfd47dfd118f3a648b39da0343691b5
49064 F20101118_AABVMN woo_k_Page_037.jpg
1a2293394ba9cdf79767c49c09a3abbd
f9d3168c29d55d9b2b060abb222554f0fbd539b6
48200 F20101118_AABWFK woo_k_Page_076.pro
da150858fec4a08d92aa9942b8ab5fdf
5d3b9487ce0173ce29557ca3089763947f08c269
38666 F20101118_AABVLZ woo_k_Page_023.jpg
17935e918b8e68cea88f480fdf34eef0
7b7cf799a17d2b8e7a1d475fb991bfd4b1fa2d00
50053 F20101118_AABWEX woo_k_Page_063.pro
6bd1603a8cd84a838838f0aabe72a291
0591b9636409cefae3d52d782bafada27b4661a6
24993 F20101118_AABVND woo_k_Page_053.jpg
1b80aa31584fd8b0e1ea8c25d82c540e
ab8cee121721775c5a493ddbe96b61f0de723d06
72827 F20101118_AABVMO woo_k_Page_038.jpg
e459c96efdd707495f3efee94465d0e2
3a3a0a892bfab22876ff6aff0c8b0362d3b67c29
49344 F20101118_AABWFL woo_k_Page_077.pro
49880fda6194a8a850e187dcdd1c24b9
f594e7881d0dc029b90c9aad1b1db8bd47289100
30699 F20101118_AABWEY woo_k_Page_064.pro
923e91cf8837c7990563d53cbed1ab09
66a25474f323bf67f47dd88dd24f2fa8d01b9787
14248 F20101118_AABWGA woo_k_Page_093.pro
14bfbd37afbc8a2d961b03bc908e46ac
55c31577efbfea9af4a8dd5a9f2f174aadc5e626
71759 F20101118_AABVMP woo_k_Page_039.jpg
cc3a76c1948e6ad3da847d66b9aca86d
4d2936482134fed5c9afadfdcb1f2e32cbe8da28
15313 F20101118_AABWFM woo_k_Page_078.pro
c2afaae45a8e3bd3c5898ea3558082b3
1061d81fb20ad635438a74b4d5a4f7db52c04412
50439 F20101118_AABWEZ woo_k_Page_065.pro
a2eb4937490d7d8039869b8e571a3776
9e23f51475e023370762eabd37b7c3a4ef328dfc
60678 F20101118_AABVNE woo_k_Page_054.jpg
48ac9208d0bd6b5649377a8ab15c5077
a691faaee377cbec8356b09001a2b25fc8b5a0fe
47292 F20101118_AABWGB woo_k_Page_094.pro
af10438751dbbc414e0426e85058e0bc
70bf7c95504e7f8d43728f5d2ec3be712017973a
39289 F20101118_AABVMQ woo_k_Page_040.jpg
c5d95f947144a3bf9b20b9b5c03f3244
3f82388b834f50946f278e3379e0eb6892b424b2
19527 F20101118_AABWFN woo_k_Page_079.pro
21104bafb90d99e8d2d640c640ac9d26
c77914f19628ed414ffa8f4997a1a1939c149a82
48318 F20101118_AABVNF woo_k_Page_055.jpg
6927270db727fe2b6b30e71a05316a22
ac2fd4472f51c686a04262122a419df7270bfea8
43172 F20101118_AABWGC woo_k_Page_095.pro
737557dabec6b21de4edbacf97f5e4f0
1de3e39619825699ac6dc1f637e74a8b7e17038b
24885 F20101118_AABVMR woo_k_Page_041.jpg
d54e20a90c883840564dd11ecc0db810
c68ec11d8ace91ac70cc7e47541639e006169f7e
12795 F20101118_AABWFO woo_k_Page_080.pro
158a4c33d01bfef6120047f2a0857e2f
67bb99b63ae6286c7acfc26f8c947ac7157ce0f5
72275 F20101118_AABVNG woo_k_Page_056.jpg
1e990420871e8269eca0b2108f547f1b
18c37623dc79d33155daccc0386aa344803e9342
52515 F20101118_AABWGD woo_k_Page_096.pro
4994acf39ac860fb75bdb010bdae80b8
794780be158e952e6e4b3d7d9a65357cd21c9416
63297 F20101118_AABVMS woo_k_Page_042.jpg
9faff59d21f35785db2b947d9636ee2e
fc79587ea412f174d4d100def62f358395a51bb1
39362 F20101118_AABWFP woo_k_Page_081.pro
839e21bfc05e231a3387044d5477fff9
5215549771ae702475c77bed998c1922cb523a28
66580 F20101118_AABVNH woo_k_Page_057.jpg
9393af7190d4de73e5244265fa6b6fc3
b7aa7355ae8e8f323300ce2526ab51fc0de14e05
49276 F20101118_AABWGE woo_k_Page_097.pro
ae4ae344ff9ea2251ca8a357b5e4da23
10b4f6db5e618db5c365d2812feed8145277b5c7
47374 F20101118_AABVMT woo_k_Page_043.jpg
e14c54bd9318ee6961db1e68a70089e1
e388dddc9ecac6e70252d5a203e1c8e0b41aeac0
44101 F20101118_AABWFQ woo_k_Page_082.pro
818bff4801bdd4e2ead1056ee533acab
3dfe5e02edb61fbf01f8dfe33e613c33afd2e844
27949 F20101118_AABVNI woo_k_Page_058.jpg
d2548130520db7870d5bd3d8b903601b
092ce31697d2362d014d7c1e59f889e64a4f6076
50428 F20101118_AABWGF woo_k_Page_099.pro
8cc7b984109ca1ebd4af2d71b224afd5
5013675e6b820f73039d5288d2b87da6b4dfc708
61340 F20101118_AABVMU woo_k_Page_044.jpg
55a36b72037e5e3a178372f1d2fda918
9ba37fd142b498a5d33b7c115f468ba224295ec7
46169 F20101118_AABWFR woo_k_Page_084.pro
e80d96e6e6eed962db4512f7e7a6241e
0d033b107288378b73c225ec170619083adb7172
65449 F20101118_AABVNJ woo_k_Page_059.jpg
72512c39aab85210fa05a9a77ff41f82
82dcf59fbd9549d5fa91bbfb015872f66112ea72
47765 F20101118_AABWGG woo_k_Page_100.pro
2df9482a61337f828fa2bb1e013f0a67
091987bc143e3a4b75b6892477c93f4b793841e1
56638 F20101118_AABVMV woo_k_Page_045.jpg
89c085b99f60a020ace3df7f1b210daa
6a32842830f478cdc420a9c0dcd8355db9e4063f
44158 F20101118_AABWFS woo_k_Page_085.pro
67fb732247d6f34b56b8585dd0a9c2d4
8246b555c0c8a2ee6f564bdb9591e8ac13fafa49
53100 F20101118_AABVNK woo_k_Page_060.jpg
d0158563b1ea9ac489be72e7227fbf2d
92749e626fb0eac7156713aa0878817f24cee8d9
14864 F20101118_AABWGH woo_k_Page_101.pro
ba3635851ba2bf0fa15c0b5ecc42617b
ffca71cf5fcea2b36b5975052607c3a8e52bcc7c
52823 F20101118_AABVMW woo_k_Page_046.jpg
bed7fedbd6ea0c66ee247dec678f2984
2ed9df26950486375f0bdfb209b19440f227ffce
34574 F20101118_AABWFT woo_k_Page_086.pro
9fb2592890a09aeb47ef3e901093e7b1
dcad59c372709b0ba7cc39ff4ff3df7e353e9c2d
55629 F20101118_AABVNL woo_k_Page_061.jpg
08ce41d6350829128b254730cc4005f5
ad2264586e9ea335862ecac41408afcfa5a31bce
11512 F20101118_AABWGI woo_k_Page_102.pro
1a525ed17c42c85012af047fe56ec3a9
b8b00897b5b3c4d41b6cc3d193d33614548d540b
52591 F20101118_AABVMX woo_k_Page_047.jpg
2de121ddb98fafc22b0a97d694b553af
5e33d900ad6ec1c4010d98e7dcff6297d3c9d5e6
32691 F20101118_AABWFU woo_k_Page_087.pro
5ceaa70b421b2e93fead65ec6f1476c5
6cdb73e84d676a5640ca48c293a74bfac8e2340e
69283 F20101118_AABVOA woo_k_Page_076.jpg
40bf845a152b9b651976b32794b84e05
d551bcd4f8fa9291c7957b5ee35883e7827328c1
57567 F20101118_AABVNM woo_k_Page_062.jpg
7fe041d0baf83f8f4c7afe9d8e33f086
9d7dff26d4a66260c514b6147870967f0679c5ed
10272 F20101118_AABWGJ woo_k_Page_103.pro
fa11eeaa9a0ed57bac931fd89eba1d9a
e004cd287a7522956047d0ca928c8a0cf712a20d
59770 F20101118_AABVMY woo_k_Page_048.jpg
d08f3d0e56b875c87a4730d57c158d0d
a9ee4e5af2f260efafb1314509dccf3b6b4fafc0
23897 F20101118_AABWFV woo_k_Page_088.pro
424f145f7ec3eeed879c49e0fa48e13b
dd9704fd14cbb3833345b60741ca84826e98da04
71349 F20101118_AABVOB woo_k_Page_077.jpg
ac4c7820ee5a69d4a6d76ac4520f49cc
5c26c621201b92dcb7d1280e75d99ab4e94e93e2
72085 F20101118_AABVNN woo_k_Page_063.jpg
ad6204b0a93e166a5b9c4223b012ca4b
8766e52ee41586a609943ca44e32f75eca121db0
42927 F20101118_AABWGK woo_k_Page_104.pro
72395d0c316e9fe93a674ab278bf542f
c68cef1892cd5a6cea4e02e30ff72d9455ffb6db
35931 F20101118_AABVMZ woo_k_Page_049.jpg
b95b0c62c54ce07821223504be9eec73
8d09ee31bf595fe432d013d1699ae9463d76e866
20626 F20101118_AABWFW woo_k_Page_089.pro
001a7d0ccbef6dcb7d320ace0ead0463
c29853edc517dfbf832b0262556aff16a0b158c4
40666 F20101118_AABVOC woo_k_Page_078.jpg
69fed2a0fe7090dd26465acb3e796354
80186f1bbbeddc821d68a783b59a66fd7e2755b5
57932 F20101118_AABVNO woo_k_Page_064.jpg
407c21f59ef9860568b6b11791e526da
f26455bc012cc1f4acda67bffd377d39b76a8276
51151 F20101118_AABWGL woo_k_Page_105.pro
4feeffa25978aa084e145bec03b0cefb
f51dbcae87be32d846ee500db7d82218c0542d72
17611 F20101118_AABWFX woo_k_Page_090.pro
f0e69e8547e2a90c739f76500542a495
e9dd12de838df0e32c8a938156c99e163afde6e1
43558 F20101118_AABVOD woo_k_Page_079.jpg
b22aa3f5a09b5f60f571b74069f7d2ae
16be4e3a90e9fe63e46c4b200ea3876e236f4ecb
70688 F20101118_AABVNP woo_k_Page_065.jpg
8ff05e0be72a3d5b5812af6d4f9ef4f4
a0815c459756c53cf158b137cd83ed9f0a6c9ae2
48404 F20101118_AABWGM woo_k_Page_106.pro
36128b1e911821f96865a0bf6568064a
6da343543192b38195431472ff59d7a742a96ca2
18333 F20101118_AABWFY woo_k_Page_091.pro
4f4b1a6e78ef85a7af00fbb5bbead971
182a58c999ce60b867be4cde94309d2f4a5c1cef
23762 F20101118_AABVOE woo_k_Page_080.jpg
821a4863e349c2219543f88a9281882e
f005e38ddb3be30ebd1073a1ee40fee2528b8e57
37017 F20101118_AABWHA woo_k_Page_121.pro
58196942f0e167ea3464c74c341452ca
78f1d8b89bf076d2997df27550aeb542ba5d89ec
44918 F20101118_AABVNQ woo_k_Page_066.jpg
d27ce54e23eb36df43edeff078e8751d
3ed0f380d804b4ae407ab203175c2770b96e4ca9
8475 F20101118_AABWGN woo_k_Page_107.pro
c807cd79a6b4de9ee2d04f023e064d21
e369275ec0e7652bad6a9e6810cf93fb6251b2ea
21337 F20101118_AABWFZ woo_k_Page_092.pro
b23b178c7e4e737b493cc619bcdd728b
37d630d4078d34f0ec81f667fca67784bc080b31
18543 F20101118_AABWHB woo_k_Page_122.pro
e22c87815011dbdccdc35ac52abec1d6
bb50a4649c20d59b6031570b038779b9b70e64f9
56493 F20101118_AABVNR woo_k_Page_067.jpg
5a569d84e50b6f4f438467271c7014e7
06f84879b7c66b370c40c9a631c1a7664fd32d16
9781 F20101118_AABWGO woo_k_Page_108.pro
2113226ff74215558f4a09944ec16441
f11930adb6584dd5f391f549de961dc990bbd653
57084 F20101118_AABVOF woo_k_Page_081.jpg
3ca571b652dbe73fea9890159b895e19
0acffaff6dae32335f8af818c27d41f52402daab
2563 F20101118_AABWHC woo_k_Page_123.pro
a086a7b2d7e535a64d2daa154f676f27
21c33f1e5d9c039e67b17416bdf202d77bc45b5c
70863 F20101118_AABVNS woo_k_Page_068.jpg
1e0891733ace2ba97b25fcf61b8f886c
91ff9b1e6673570cf9c7db5f025b22e18beff374
9290 F20101118_AABWGP woo_k_Page_109.pro
c2fc28e3e089388f3eedbc23605de365
ae867f76233ce845c4149f1149ed42f390a56cca
64428 F20101118_AABVOG woo_k_Page_082.jpg
0d907ae414c65f48d08ee0c4cd3371d5
d0c0ea70d9063861eaa255379ceaa7b1c630e36d
40562 F20101118_AABWHD woo_k_Page_124.pro
9b620fbf50f8df74e0e22a60e2f4fefb
2babf4590eaadaf6724b791b7193644486d03e4f
44583 F20101118_AABVNT woo_k_Page_069.jpg
1336afe27e32b18b50e50d4cc5a8aa07
ee5fed5eed60126a7f1656edabbca953dfcb4d77
5102 F20101118_AABWGQ woo_k_Page_110.pro
52b33340d50946405dd3e49a92c85cee
b08d36f9f8488d6c3b0c0ff2bc814ce986c7c732
57111 F20101118_AABVOH woo_k_Page_083.jpg
28d72677c6204f696e5c75fd70523ac8
595c1bc13a97552c89756b96b5a1457d93c6ad82
2543 F20101118_AABWHE woo_k_Page_125.pro
794874ff1882a2cbb680bd543fe23af8
e947a9f364bb46afd10740bbaec0f5821e6d8f46
48598 F20101118_AABVNU woo_k_Page_070.jpg
6e72718b27b188dfaddcb9765381cc59
f082c21ab39d15a5daf5fae9b6503aab4bc5d8ba
3023 F20101118_AABWGR woo_k_Page_111.pro
989bcdcde0c3a431eee8d7fd5878c5df
ab4dc441e0567e3e0a82eef96d7075c0f13ebc10
64843 F20101118_AABVOI woo_k_Page_084.jpg
9c6735cdd291f69c7a08bfcd51437be4
da53b73a71af8b10024426f300d8908c925b0f2e
36499 F20101118_AABWHF woo_k_Page_126.pro
f92eee3d3e54b8e709d06e2674a48e10
2da22136e8a163c7324ccda8a2bfd661f22e8b8e
66140 F20101118_AABVNV woo_k_Page_071.jpg
7d77547281bdf858d39764edaece5cd7
51e41acbe25477e558390dd98e0a58fb83737f81
6418 F20101118_AABWGS woo_k_Page_112.pro
4fe418dc7d201281a8d3395f41944689
5f34e451cc98ca3644487c0806a5b8ea0aed6177
62580 F20101118_AABVOJ woo_k_Page_085.jpg
0f79671277c3c0cf1da5ae6dfe539959
e0dbac2665add7187fb5efa9e69b57f6ffe793ff
5183 F20101118_AABWHG woo_k_Page_127.pro
6ed8eecd593d2226a8201d59b2a9b993
223491342a53871fedca26fb7498dff5e673fd6c
55044 F20101118_AABVNW woo_k_Page_072.jpg
14a89096533b98994a0b88173659ab9f
8417e4c5b6c7b66e38ac1f7b9592d13c0e2a0d29
5870 F20101118_AABWGT woo_k_Page_113.pro
e85ce6a0b460f43abe89614dc7f81bd1
00a404a064408c7b42aa82ee0a0ca1de4e7f090a
60024 F20101118_AABVOK woo_k_Page_086.jpg
8e2e03f3c97e023abd26376283bb5f58
d6b79bc88d817e478ed4f57fae591b7f15fd42fe
40050 F20101118_AABWHH woo_k_Page_128.pro
c942ce99cfbbd081a58de18207b832d8
ca0e964863a96de272bd15af9c3f631c12abf168
52539 F20101118_AABVNX woo_k_Page_073.jpg
ad20e054688dce9febee4c52ba732b05
7bbb35cbdf38d1ddab56221d604f2b41f6f89bab
5858 F20101118_AABWGU woo_k_Page_114.pro
32dd764bb6a44a71b19ba894428e4477
6502787bd7278d0d71a899b9a2f5e6a4a124ae74
35666 F20101118_AABVPA woo_k_Page_103.jpg
d3ee913560416b4a154d9ac13b256bdd
056d0f91caafe8b0f6b991e6f699e7e0f56bbe0e
56937 F20101118_AABVOL woo_k_Page_087.jpg
52bea648d2c22c39d35e570ae695f19a
e410f04e0887491d30c6bea8d2fe6343e47baf68
2190 F20101118_AABWHI woo_k_Page_129.pro
0a57c03f4c4015f30853f51e9a3b4545
982c59fafad18b652f40e017aca688ffccb3c6c9
53457 F20101118_AABVNY woo_k_Page_074.jpg
f092a95d375dc67254f7b46e9513c44c
c26134a7fb6c95136a21ac0a448a5f0773a86c87
5637 F20101118_AABWGV woo_k_Page_115.pro
9753ee7f2e3ed164d1fe74ccb756ee0a
9b7774ba068405208862121cb0fd8724ee6c97ed
62364 F20101118_AABVPB woo_k_Page_104.jpg
516abbb37c2e6b42d70697991344c376
4f48e05340437019ddd1dcc4bebf0a91c2d9e996
47383 F20101118_AABVOM woo_k_Page_088.jpg
dc47264e38ff86ded9ff228c74282f1e
811b3b2a2fd2d5bfe8b4e259adf0cdb528c33e24
38714 F20101118_AABWHJ woo_k_Page_130.pro
e96b01b368f2c10f9db8374ef96f477b
f9ae23c70f1cfb6eaa3aa62a8159e808f7e82e4b
62718 F20101118_AABVNZ woo_k_Page_075.jpg
23fc7696cc92a33d1cd6d94a455197a9
2963a45b87b9e1d513bd1b4ccb6ec2a78ecbc348
8839 F20101118_AABWGW woo_k_Page_117.pro
0ae2f7e985ca6ac37b9a037114013f53
569983f2031a97d4b8cefcd68e7fcf3239f3a9da
71896 F20101118_AABVPC woo_k_Page_105.jpg
722e2b36e90af84eb5fc3cc6792af8d1
d90bc746e89983ac977771bbca0de9806328115c
47762 F20101118_AABVON woo_k_Page_089.jpg
4ecd3ef4c1dd18488a6c65cc11906e0e
8d3af7d95ec3f58afb0360cd0b70a2933e274091
7458 F20101118_AABWHK woo_k_Page_131.pro
0ad7951401893719d366ea3acddd5a2d
b53094e418bbb8ba9c1da0f2810a0d52b63fe9f0
8584 F20101118_AABWGX woo_k_Page_118.pro
1e01ce14ce4b088763e6f29f4a758f4d
ba5deae5ac3fd199b411e2373b25c2b7179b1420
68078 F20101118_AABVPD woo_k_Page_106.jpg
82c64f84123c07bc6cc9e4286296c178
10ae753ad7f5bc68a462474c18355224254f0efb
43776 F20101118_AABVOO woo_k_Page_090.jpg
225e946931743ebbb1bca45feb11bd17
c0882b691b21ecdae14f950036cb5ec5292f0288
7292 F20101118_AABWHL woo_k_Page_133.pro
e71826113af1abc41ee66fdbf7183997
6cf6d5624bfe777d8bfb7a74d5f3524da684f4c1
2865 F20101118_AABWGY woo_k_Page_119.pro
f7d5bc1ba62d56527da1ad79ca846d00
9f0d76533228921164a2e6ea5e3067640848e4ef
18665 F20101118_AABVPE woo_k_Page_107.jpg
65d037467b18374de5e37979dbcf190a
c6fbfde95d941c13fd5a3f1a289ba330ca3ad884
3054 F20101118_AABWIA woo_k_Page_150.pro
ee04f41f3f4e3462d66fb6fde40db59a
49e43a593e213e4e8d9a42c11d23e1b3a9da0683
46995 F20101118_AABVOP woo_k_Page_091.jpg
e5c1012351011145af4058f46f68995e
befcc880665e191be2279df2158642091003424a
39761 F20101118_AABWHM woo_k_Page_134.pro
24d4ba610462fc7ef42b54908cd43eee
d677fd3257e82aa6094fbf533e99c9345bbee167
7175 F20101118_AABWGZ woo_k_Page_120.pro
a8e93321b6bee9db2a0f5b52a84dc022
fcf5906de401ee30f83559a66942a3e4fd23a43a
27026 F20101118_AABVPF woo_k_Page_108.jpg
282d03af4c73225b37a8c0b037d0f633
a548a5afd8d93cb159de73939a09ddce49333332
5069 F20101118_AABWIB woo_k_Page_151.pro
180ade0e4b061b8aa5edd68595afcb7e
daf02a75b9a5375d53d0151c524482e22f5ff3a3
43697 F20101118_AABVOQ woo_k_Page_092.jpg
60983c1d51d5e1e5046b10a050d5adb9
d8504ec61eb6b8ec640d4bba552d98c98bcbf6c0
9607 F20101118_AABWHN woo_k_Page_135.pro
ba893870725f4433640092f1bfdf1bc1
77727b419c469870b266385d8897d43baa091fd6
4110 F20101118_AABWIC woo_k_Page_152.pro
cfe99ea30dfb94f169acd5efc52de058
f3dd1c1a8bb77dd032b6e89d169f27e44371394c
F20101118_AABVOR woo_k_Page_093.jpg
6b1f81451e28f296a63963b13070dbf0
0c055fece64ff26fa4fc19a90fb3b2261fa01eb4
44482 F20101118_AABWHO woo_k_Page_138.pro
737e1cd2363f9c129cb8631e2e85f6ef
4e84fb5744b4bd1927a4363524cf3d303381da5b



PAGE 1

TRANSMISSION PROPERTI ES OF SUB-WAVELENGTH HOLE ARRAYS IN METAL FILMS By KWANGJE WOO A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2006

PAGE 2

Copyright 2006 by Kwangje Woo

PAGE 3

iii ACKNOWLEDGMENTS For last 5 years for my Ph.D. work, there are many people whom I have to thank for their support, advice and encouragement. First, I would like to thank my advisor, Professor David B. Tanner. Since I have become his research assistant, I have receiv ed so much valuable advice, encouragement and support. Also, I would like to thank Professor Arthur F. Hebard, Professor Stephen O. Hill, Professor Selman P. Hershfield and Prof essor Paul H. Holloway for serving on my supervisory committee. It was a great time for me to work in Prof Tanner’s lab for last four years because I had good colleagues in this lab: Dr. Andrew Wint, Dr. Hedenori Tashiro, Dr. Maria Nikolou, Dr. Minghan Chen, Haidong Zhang, Naveen Margankunte, Nathan Heston, Daniel Arenas and Layla Booshehri. I would like to th ank these people. Especially, I would like to thank my collaborator Sinan Selcuk for supplying samples, scientific discussi ons and a truthful friendship. I would like to thank my parents. They have supported me throughout my life. Finally, my wife and children, Ohsoon, Jis oo and Jiwon, have supported me with their love and patience. I would like to ex press my deepest thanks to them.

PAGE 4

iv TABLE OF CONTENTS page ACKNOWLEDGMENTS.................................................................................................iiiLIST OF TABLES............................................................................................................viiLIST OF FIGURES.........................................................................................................viiiABSTRACT......................................................................................................................x ii CHAPTER 1 INTRODUCTION........................................................................................................1Background and Motivation.........................................................................................1Organization.................................................................................................................22 RIVIEW OF SURFACE PLASMO N AND DIFFRACTION THEORY....................4Bethe’s Theory for Transmittance of a Single Sub-Wavelength Hole.........................5Surface Plasmon...........................................................................................................7Definition of Surface Plasmon..............................................................................7Dispersion Relation of Surface Plasmon...............................................................7Dispersion relation for the p-polarization......................................................8Dispersion relation for the s-polarization.....................................................10Dispersion curves.........................................................................................12Propagation Length of the Surface Plasmon.......................................................14Surface Plasmon Excitation.................................................................................14Mechanism of Transmission via Surface Plasmon Coupling in Periodic Hole Array................................................................................................................17CDEW (Composite Diffractive Evanescent Wave)...................................................19Basic Picture of the CDEW.................................................................................19CDEW for an Aperture with Periodic Corrugation.............................................22CDEW for a Periodic Sub-Wavelength Hole Array............................................23Fano Profile Analysis.................................................................................................253 INSTRUMENTATION..............................................................................................29Perkin-Elmer 16U Monochromatic Spectrometer......................................................29Light Sources and Detectors................................................................................29

PAGE 5

v Grating Monochromator......................................................................................30Monochromator configuration.....................................................................31Resolution of monochromator......................................................................32The Diffraction Grating.......................................................................................33Grating equation and diffraction orders.......................................................33Blaze angle of the grating.............................................................................34Resolving power of grating..........................................................................34Bruker 113v Fourier Transform In frared (FTIR) Spectrometer.................................35Interferometer......................................................................................................35Description of FTIR Spectrometer System.........................................................384 SAMPLE AND MEASUREMENT...........................................................................41Sample Preparation.....................................................................................................41Substrates....................................................................................................................4 1Measurement Setup....................................................................................................435 EXPERIMENTAL RESULTS...................................................................................46Enhanced Optical Transmission of Subwavelength Periodic Hole Array................46Comparison of Enhanced Transmission w ith Classical Electromagnetic Theory......47Dependence of Period, Film Thickness and Substrate on Transmission....................48Dependence on Period of Hole Array.................................................................49Dependence on the Thickness of Metal Film......................................................50Dependence on the Substrate Material................................................................52Dependence on the Angle of Incidence......................................................................54Dependence on Hole Shape........................................................................................58Square Hole Arrays.............................................................................................58Rectangular Hole Array.......................................................................................59Slit Arrays............................................................................................................61Transmission of Square Hole Array on Rectangular Grid..................................62Refractive Index Symmetry of Dielectric Materials Inte rfaced with Hole Array......636 ANALYSIS AND DISCUSSION..............................................................................68Prediction of Positions of Transmission Peaks...........................................................68Comparison of Calculated and Measured Positions of Transmittance Peaks and Dips.........................................................................................................................70Dependence of the Angle of Incidence on Transmission...........................................74Drawbacks of Surface Plasmon and CDEW..............................................................82Dependence of Hole Shape, Size and Polarization Angle on Transmission...............84CDEW and Trapped Modes for Transm ission Dependence on Hole Size.................877 CONCLUSION...........................................................................................................91APPENDIX A TRANSMITTANCE DATA OF DOUBLE LAYER SLIT ARRAYS......................95

PAGE 6

vi B POINT SPREAD FUNCTIONS AND FOCUSING IMAGES OF PHOTON SIEVES.....................................................................................................................107C TRANSMITTANCE DATA OF BULL’S EYE STRUCTURE..............................136LIST OF REFERENCES.................................................................................................142BIOGRAPHICAL SKETCH...........................................................................................146

PAGE 7

vii LIST OF TABLES Table page 4-1 List of the periodic sub-wavelength hole arrays......................................................436-1 Calculated positions of surface plasm on resonant transmittance peaks for three interfaces of 2000 nm period hole arrays at normal incidence ( d of air, fused silica and ZnSe are 1.0, 2.0 and 6.0, respectively)...................................................696-2 Calculated positions of transmittance dips for three interfaces of 2 m period hole arrays at normal incidence ( d of air, fused silica and ZnSe are 1.0, 2.0 and 6.0, respectively)......................................................................................................72

PAGE 8

viii LIST OF FIGURES Figure page 2-1 Schematic diagram for p-polarized (TM) light incident on a dielectric/metal interface....................................................................................................................122-2 Schematic diagram for s-polarized (TE) light incident on a dielectric/metal interface....................................................................................................................122-3 Dispersion curves of surface plasmon at air/metal interface and at quartz/metal interface, light lines in air and fused silica...............................................................132-4 Schematic diagrams of (a) the excitati on of the surface plasmon by the incident photon on a metallic grating surface and (b) th e dispersion curves of the incident photon, the scattered photon and the surface plasmon.............................................152-5 Schematic diagrams of the excitation of the surface plasmon by the incident photon on a two dimensional metallic grating surface.............................................182-6 Schematic diagram of transmission mechanism in a sub-wavelength hole array....182-7 Geometry of optical scattering by a hole in a real screen in (a) real space and (b) k-space for a range that kx is close to zero................................................................212-8 CDEW lateral field profile at z = 0 boundary, a plot of Eq. (2-44) .........................222-9 CDEW picture for an aperture with periodic corrugati ons on the input and output surfaces. Red arrows indicate the CDEWs generated on the input and output surfaces..........................................................................................................242-10 A CDEW picture for a periodic subwavelength hole array. Red arrows indicate the CDEWs generated on the input and output surfaces..........................................242-11 Schematic diagrams for Fano profile analysis.........................................................272-12 A schematic diagram of the non-resona nt transmission (Bethe’s contribution) and the resonant transmission (s urface plasmon contribution)................................272-13 Schematic diagram of the interference between the resonant and non-resonant diffraction in transmission of sub-wavelength hole array........................................283-1 Schematic diagram of Perkin-Elmer 16U monochromatic spectrometer.................30

PAGE 9

ix 3-2 Schematic diagram of the Littrow co nfiguration in the monochromator of Perkin-Elmer 16U spectrometer...............................................................................313-3 Schematic diagram of a reflection grating...............................................................333-4 Schematic diagram of a blazed grating....................................................................343-5 Schematic diagram of Michelson interferometer.....................................................363-6 Schematic diagram of the Bruker 113v FTIR spectrometer.....................................394-1 SEM images of periodic hole arrays samples..........................................................424-2 Picture of the sample holder used to measure transmittance with changing the angle of incidence and the in-plane azimuthal angle...............................................445-1 Transmittance of the square hole array (A14-1) and a silver film...........................475-2 Comparison between Bethe’s calculati on and the transmittance measured with the square hole array (A14-1)...................................................................................485-3 Transmittance of square hole arrays w ith periods of 1 m (A15) and 2 m (A181)............................................................................................................................. ..495-4 Transmittance vs. scaling variable, s = /( nd period), for the square hole arrays of 1 m period (A15) and 2 m period (A18-1) made on fused silica substrates ( nd = 1.4)..................................................................................................515-5 (a) Transmittance vs. wavelength (b) transmittance vs. scaling variable, s = /( nd period), for the square hole arrays of 2 m period (A14-1) made on a fused silica substrate ( nd = 1.4) and a ZnSe substrate ( nd = 2.4)..............................535-6 Transmittance of a square hole array (A14-1) with three different polarizations at normal incidence..................................................................................................545-7 Measurement of transmittance with s-polar ized incident light as a function of the incident angle...........................................................................................................565-8 Measurement of transmittance with p-pol arized incident light as a function of the incident angle.....................................................................................................575-9 Transmittance of square hole array (A181) as a function of polarization angle. The inset shows a SEM image of the square hole array...........................................595-10 Transmittance of a rectangular hole array (A18-2) for in-plane polarization angles of 0 and 90 The inset shows a SEM imag e of the rectangular hole array.......................................................................................................................... 60

PAGE 10

x 5-11 Transmittance of a slit array (A18-3) for in-plane polarization angles of 0 and 90 The inset shows a SEM im age of the slit array...............................................615-12 Transmittance of a square hole array on a rectangular grid (A18-4) for polarization angles of 0 45 and 90 The inset shows a SEM image of the square hole array in a rectangular grid.....................................................................625-13 Schematic diagram of sample preparation...............................................................655-14 Transmittance of a square hole array (A 14-1) on fused silica substrate with and without PR coated on the top...................................................................................655-15 Transmittance of a square hole arra y (A14-1) on ZnSe substrate with and without PR coated on the top of hole array..............................................................665-16 Transmittance of a square hole array (A 14-1) on fused silica substrate with and without PMMA coated on the top of hol e array with the second fused silica substrate attached on the top of PMMA...................................................................666-1 Comparison of calculated peak positions with measured transmittance data. Transmittance measured with a square hol e array (A18-1) is shown. P1, P2 and P3 are the calculated positions of three transmittance peaks...................................706-2 Comparison of the calculated tran smittance peaks and dips with the transmittance measured with a square hole array (A18-1) made on a fused silica substrate. P1, P2 and P3 are the calculate d positions of the first three peaks and D1, D2 and D3 are the calculated po sitions of the first three dips...........................736-3 Comparison of the calculated tran smittance peaks and dips with the transmittance measured with a square hole array (A14-1) made on a ZnSe substrate. P4 and P5 are the calculated peak positions and D4 and D5 are the calculated dip positions for the ZnSe-metal interface. P2, P3, D2 and D3 are the positions of the peaks and the dips for the air-metal interface.................................746-4 Transmittance of a square hole array (A14-1) measured using unpolarized light at normal incidence..................................................................................................756-5 Schematic diagram of an excitation of surface plasmon by the incident light on two dimensional metallic grating surface.................................................................766-6 Transmittance with s-po larized incident light..........................................................776-7 Transmittance with s-po larized incident light..........................................................786-8 Peak and dip position vs. incident angle for s-polarization......................................796-9 Peak and dip position vs. incident angle for p-polarization.....................................80

PAGE 11

xi 6-10 Transmittance of square, rectangular and slit arrays with polarization angle of 0 ..............................................................................................................................8 96-11 Transmittance of square, rectangular and slit arrays with polarization angle of 90 ............................................................................................................................90

PAGE 12

xii Abstract of Dissertation Pres ented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy TRANSMISSION PROPERTI ES OF SUB-WAVELENGTH HOLE ARRAYS IN METAL FILMS By Kwangje Woo August 2006 Chair: David B. Tanner Major Department: Physics We have measured the optical transmittance of sub-wavelength hole arrays in metal films. We investigated the spectral behavior of transmittance (the peak positions, intensities, line-widths, and the dip positions) as a function of the geometrical parameters of the hole arrays, the angle of incidence, the polarization angle and the refractive indices of the substrates. We calculated the positions of transmittance peaks and dips with equations from the surface plasmon theory and the diffraction theory, and compared the calculated positions of peaks and dips with measured transmittance data. We found that there is a discrepancy of 3 ~ 5% between the peak positions calculated with the surface plasmon equation and the peak positions in the measured transmittance data. We explain this discrepancy as possibly due to the a pproximations of the surface plasmon equation. However, the positions of the dips in the spec tra, as calculated with the diffraction grating equation, were well matched to the measured da ta. We also observed sp littings and shifts of the peaks and dips when changing the angl e of incidence and th e polarization of the

PAGE 13

xiii light. We confirmed this spectral behavior qualitatively with calc ulation of momentum conservation equations for oblique incidence and showed that the diffraction modes are degenerate for s-polarization, while the mode s are not degenerate for p-polarization. We studied the dependence of hole size and shap e on the transmittance while also changing the in-plane polarization angl e. We observed that the tr ansmittance peak is strongly dependent on the length of the hole edge pe rpendicular to the polar ization direction. In addition, we investigated the dependence on f ilm thickness and the refractive index of dielectric substrate.

PAGE 14

1 CHAPTER 1 INTRODUCTION Background and Motivation Recently, many workers in the area of optics have reported very interesting results in a new regime of optics called nano optics, sub-wavelength optics, or plasmonic optics [1]. In this area of optics, the physical dime nsion of objects for optical measurements is on a sub-wavelength scale. In terestingly, the optical prop erties of sub-wavelength structures are different from what we predict from classi cal electromagnetic theory [2]. In addition, this new field of optics makes it pos sible to manipulate lig ht via sub-wavelength structures. This capability of controlling light attracts a lot of applications in various fields of science and technology, for instan ce, Raman spectroscopy, photonic circuits, the display devices, nanolithography and biosensors [3-6]. Since the first research on enhanced op tical transmission of an array of subwavelength holes was reported in 1998 by Ebbesen et al. [7], no theory has explained this phenomenon, even though a lot of work has b een carried out. But theoretical studies are still actively going on, with the most promin ent one being the surface plasmon polariton (SPP) theory [8]. In addition to the surf ace plasmon polariton, the diffraction theory is also a very strong candidate as an explan ation of the enhanced transmission of subwavelength hole array [9-11]. Another model [ 12-14] proposed to explain this enhanced transmission phenomenon is the superpositi on of a resonant process and a non resonant process which shows the Fano profile [15]. Since the surface plasmon polariton model has some drawbacks [9] and shows a discrepa ncy between calculated and measured data

PAGE 15

2 [16], other models are consider ed as strong explanations of this enhanced transmission phenomenon. Many experiments also have been done for a wide spectral range. The enhanced transmission of periodic hole arrays for the optical region, the near -infrared region [17], and the terahertz (THz) re gion [18-24] was reported. Other scientific and technol ogical interest is focused on the enhanced transmission of a single sub-wavelength aperture. The enhanced transmission of a single plain rectangular aperture, which de pends on the polarization dire ction, was reported [25, 26]. And an aperture with corrugations on the inpu t side showed an enhanced transmission as well as a beaming of the transmitted light wi th corrugations on the output side [27-29]. In this dissertation, we present experime ntal transmission data for sub-wavelength hole arrays as a function of their geometrical parameters, the angle of incidence, the polarization of the light, and for two values of the refract ive index of the dielectric substrate material. For the theoretical models, we will discuss surface plasmon, composite diffractive evanescent wave, Fa no profile analysis and trapped mode. Organization This dissertation consists of seven chapters, including this introduction chapter. The details of each chapter are as follows: In Chapter 2, we review the basic theori es of surface plasmon and diffraction. The surface plasmon theory includes surface plasmon excitation by incident light, the plasmon dispersion relation, and an introduc tion of the transmission mechanism via surface plasmon coupling. The diffraction theory includes th e CDEW (composite diffractive evanescent wave) model and Fano profile analysis. In Chapter 3, we describe our experimental setup for transmission m easurement. Two spectrometers (a grating

PAGE 16

3 monochromatic spectrometer a nd a FTIR spectrometer) are introduced. In Chapter 4, the sample preparation and the measurement techni que with the specifications of samples are presented. In Chapter 5, the measured transmittance da ta are presented. The transmittance data are shown as a function of the geometrical pa rameters of hole arra y, the polarization and the incident angle of light, and the refr active indices of the substrate material. In Chapter 6, we analyze and discuss th e experimental results based on the surface plasmon and diffraction theories. We discuss the positions of peaks and dips, spectral changes with variation of the incident angl e and polarization, a nd the dependence on hole shape and size. Finally, Chapter 7 has the c onclusions of this di ssertation and briefly introduces some additional studies which are necessary for a future study.

PAGE 17

4 CHAPTER 2 RIVIEW OF SURFACE PLASMON AND DIFFRACTION THEORY There are two independent theories whic h explain the transmission enhancement by periodic arrays of sub-wavelength hole s: the surface plas mon polariton and the diffraction theory. When the enhanced transm ission was reported by Ebbesen and his coworkers, they interpreted their results with the surface plasmon [7]. The surface plasmon is still the most generally accepted explan ation of the enhanced phenomenon [30-33]. With dispersion relation of th e surface plasmon and momentum conservation equation of periodic grating, one can predict the positions of the enhanced transmission peak pretty accurately. But the prediction still shows some differences with the experimental results [16]. For this difference, there might be two reasons. First, the surface plasmon theory is based on the long-wavelength approximation ( >> d ), which means that it does not depend on the hole size of the structures. S econd, the surface plasmon theory, which is currently used in most papers, is still lim ited to the dispersion relation for a single interface between a dielectric and a metal (in which both are infinitely thick) while the experiments deal with structur es containing double interfaces with a finite thickness for the metal film [34] As we know, the classical diffraction theory for an electromagnetic wave impinging on a sub-wavelength aperture in an optic ally opaque conducting plane predicts an extremely low transmittance [2]. In this paper, Bethe showed the transmittance intensity of a sub-wavelength aper ture proportional to ( d / )4. But many calculations for diffraction

PAGE 18

5 by periodic hole arrays show an enhanced transmission which is very similar to experimental data [35-38]. The composite diffractive evanescent wave (CDEW) [9] is one of the diffraction models explaining the enhanced transmission by periodic structures The CDEW means a constructive interference of electromagnetic waves diffracted by periodic sub-wavelength structure and it is another st rong candidate responsible for the enhanced transmission phenomenon. This diffraction model (CDEW) can explain the enhanced transmission of hole array in a perfect conductor or in non-me tallic materials which the surface plasmon model cannot explain. Another transmission model e xplaining the enhanced tran smission is a unifying one of both the surface plasmon and the diffrac tion model [12, 13]. This unifying model proposes an analysis with Fano profile in tr ansmission spectra which is attributed to a superposition of the resonant pr ocess and non-resonant process. Recently, A. G. Borisov et al. [39] pr oposed another diffraction model for the enhanced transmission of sub-wavelength stru ctures. They suggested that the enhanced transmission of sub-wavelength hole arrays is due to the interference of diffractive and resonant scattering. The contribution of th e resonant scattering comes from the electromagnetic modes trapped in the vicinity of structures. This trapped electromagnetic mode is a long-lived quasista tionary mode and gives an explanation of extraordinary resonant transmission. Bethe’s Theory for Transmittance of a Single Sub-Wavelength Hole Bethe [2] reported that the transmittance of electromagnetic waves through a single hole in an infinite plane c onducting screen, which is very thin but optically opaque, is very small when wavelength of the incident li ght is much larger than the hole size. With

PAGE 19

6 this long-wavelength condition, d / << 1, where d is the diameter of hole and is wavelength of the incident light, Bethe has ca lculated “diffraction cross section” of the hole for the sand p-polarization: cos 2 27 646 4 d k As (2-1) 2 6 4sin 4 1 1 2 27 64 d k Ap (2-2) The s-polarized (TE mode) wave has an elec tric field perpendicu lar to the plane of incidence whereas the p-polarized (TM mode) wave has a magnetic field perpendicular to the plane of incidence. These polarizations are schematically shown in Figures 2-1 and 22. In Eqs. (2-1) and (2-2), one can recognize that the diffraction cross sections for two polarizations are the same for normal incidence, = 0. If the diffraction cross section is normalized to hole area, the normalized diffraction cross section becomes T d kd d A 4 4 2 223 2 27 64 2 (2-3) where 2 k k and are wave number and wavele ngth of the incident wave, respectively, and d is diameter of hole. This normaliz ed diffraction cross section can be considered as transmission normalized to hole area, T Eq. (2-3) is actually an expression for a circ ular aperture. If we change the circular aperture to a rectangular aper ture which has a dimension of D D Eq. (2-3) can be changed as

PAGE 20

7 T D kD D A 4 6 4 218 2 27 64 (2-4) Surface Plasmon The presence of a surface or an interface be tween materials with different dielectric constants leads to specific surface-related excitations. One example of this phenomenon is the surface plasmon. The interface betw een a medium with a positive dielectric constant and a medium with negative dielectric constant, such as a metal, can give rise to special propagating electromagnetic waves cal led surface plasmons, which stays confined near the interface. Definition of Surface Plasmon Sometimes the surface plasmon is also called the surface plasmon polariton. To understand this surface plasmon polariton, we need to define some terms: plasmon, polariton and surface plasmon. First, a plasm on is the quasiparticle resulting from the quantization of plasma oscillations. They ar e collective oscillations of the free electron gas. If this collective oscillation happens at the surface of metal, it is called a surface plasmon. Therefore, we define the surface plasmon as a collective oscillation of free electrons at the interf ace of metal and insulator [8]. The surface plasmon is also called the surface plasmon polariton. A polariton is the quasiparticle resulting from strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation. Therefore, if an electromagnetic wave ex cites the surface plasmons on a metal surface and is coupled with the surface plasmon, it is called the surface plasmon polariton. Dispersion Relation of Surface Plasmon To get the dispersion relation for surface plas mons [8, 34, 40], we need to consider an interface between two semi -infinite isotropic media w ith dielectric functions, 1 and 2.

PAGE 21

8 The x and y axes are on a plane of the interface and the z axis is perpendicular to the interface. Medium 1 (dielectric function 1) and medium 2 (dielectric function 2) occupy each half of the space, z > 0 and z < 0, respectively. The electromagnetic fields for the surface wave which propagate in the x direction and are confined in the z direction on this interface are of the form: 01) ( 0 z e ez t k ix E E (2-5) 02) ( 0 z e ez t k ix E E (2-6) where E> and E< are electromagnetic fields in each half space, E0> and E0< are amplitudes, is angular frequency, t is time, kx is the wave vector of su rface wave propagating along the x -axis and 1, 2 are positive real quantities. Dispersion relation for the p-polarization For p-polarized electromagnetic wave (TM wave), the magnetic field is perpendicular to the plane of incidence and the electric field is in the plane of incidence. In Figure 2-1, the H-field is along the y -axis and the E-field is in the x-z plane. Thus, the E and H fields in each region can be expressed as 0 01) ( z e e B A,z t x k ix 1E (2-7) 0 0 01) ( z e e C, ,z t x k ix 1H (2-8) 0 02) ( z e e E D,z t x k ix 2E (2-9) 0 0 02) ( z e e F, ,z t x k ix 2H (2-10) The boundary condition that needs to be c onsidered is that the components of E and H parallel to the surface are continuous at the interface, z = 0, that is 0 2 0 1 z x z xE E (2-11)

PAGE 22

9 0 2 0 1 z x z xH H (2-12) Substituting Eq. (2-7) through Eq. (2-10) into Eq. (2-11) and Eq. (2-12), the boundary conditions give A = D and C = F One of the Maxwell’s equations for continuous media is t c E H (2-13) For region 1 and 2, the x components in Eq. (2-13) give 01 1 z A c i C (2-14) 01 1 z D c i F (2-15) With A = D and C = F, division of Eq. (2-14) by Eq. (2-15) gives 2 1 2 1 (2-16) This equation is a condition for the surface plasmon mode and demonstrates that one of the two dielectric functions must be negativ e, so that, for example, the interface of metal/vacuum or metal/dielectric supports the surface plasmon mode. To get the dispersion relation of the surface plasmon, we use two Maxwell’s equations: t c E H (2-13) t c H E1 (2-17) Operating on both sides of Eq. (2-17) and substituting for H from Eq. (2-14) gives

PAGE 23

10 2 2 2) ( 1 ) ( t c t c E H E (2-18) Using E E E2) ( ) ( and 0 E for a transverse wave, we get the transverse wave equation: 2 2 2 2t c E E (2-19) In the region of z > 0, the x and z components of the solution of Eq. (2-19) are x -component: A c ikB A2 2 1 1 1 2 (2-20) z -component: B c B k A ikx x 2 2 1 2 1 (2-21) Combining Eq. (2-20) and (2-21), we get 02 2 1 2 1 z c kx (2-22) Similarly, in the region of z < 0: 02 2 1 2 1 2 z c kx (2-23) Combining Eqs. (2-16), (2-22) and (2-23) we obtain the dispersion relation of the surface plasmon: 2 1 2 1 c kx Dispersion relation of surface plasmon (2-24) Dispersion relation for the s-polarization As shown in Figure 2-2, the s-polarization has the E field perpendicular to the plane of incidence and the H field in the plane of incidence. Then, we have a set of E and H fields:

PAGE 24

11 0 0 01) ( z e e A, ,z t x k ix 1E (2-25) 0 01) ( z e e C B,z t x k ix 1H (2-26) 0 0 02) ( z e e D, ,z t x k ix 2E (2-27) 0 02) ( z e e F E,z t x k ix 2H (2-28) As in the p-polarization case, we apply the boundary conditions Eqs. (2-11) and (212) and get A = D and B = E Then we use the Maxwell’s equation: t c H E1 (2-29) Solving Eq. (2-29) with Eq. (2-25) through Eq. (2-28) for both regions of z > 0 and z < 0 give solutions with x and z components for each region: x-component: 0 z A i c B 1 (2-30) z-component: 0 z A c k Cx (2-31) x-component: 0 z D i c E 2 (2-32) z-component: 0 z D c k Fx (2-33) With the results from the boundary conditions, A = D and B = E Eqs. (2-30) through (233) can be combined and simplified 0 A2 1 i c (2-34) Since we defined 1 and 2 positive, thus A = 0 and all other constants ( B C D E and F ) also become zero. Therefore, the surface plasmon mode does not exist for the spolarization.

PAGE 25

12 Figure 2-1. Schematic diagram for p-polarized (TM) light incident on a dielectric/metal interface Figure 2-2. Schematic diagram for s-polarized (TE) light incident on a dielectric/metal interface Dispersion curves Figure 2-3 shows the dispersion curves of surface plasmons at the interface of metal/air, metal/quartz and the light lines in vacuum and fused silica glass, respectively. The momentum k is calculated by Eq. (2-24). The dielectric constant of metal, 2, in the Eq. (2-24) is described by the Drude dielectric function [41]: Metal 2 E Ex EzH k0z x Dielectric 1 Metal 2 H Hx HzE k0z x Dielectric 1

PAGE 26

13 2 2 2 2 21 1p p (2-35) where p is the bulk plasma wa velength of the metal ( p is the bulk plasma frequency). p is 324 nm for the silver film used in this experiment. The dielectric constants of air and fused silica substrate are 1.0 and 2.0, respectively. In Figure 2-3, the thickness of the metal film is considered to be infinite; thus, the interaction of the surface plasmons on both in terfaces is ignored. But if the thickness is finite, then there will be an interaction between two surface plasmons which will distort the dispersion curves of surface plasmons [34] Figure 2-3. Dispersion curves of surface plasmon at air/metal interface and at quartz/metal interface, light lin es in air and fused silica

PAGE 27

14 Propagation Length of the Surface Plasmon The propagation length of the surface plasmon can be defined by the imaginary part of the wave vector kxi in Eq. (2-24) as follows [8, 34, 40] xi xk L 2 1 (2-36) The dielectric function 2 is a function of At each it is a complex number, i ri2 2 2 where 2r and 2i are the real and the imaginar y parts of the dielectric function. The wave vector kx is also a complex number, xi xr xik k k 2 1 2 1 2 1 r r xrc k (2-37) 2 2 2 2 3 2 1 2 12r i r r xic k (2-38) From Eqs. (2-30) and (2-32), we can get the propagation length of the surface plasmon: i r r r xc L2 2 2 2 3 2 1 2 1 (2-39) Using parameters for silver [42], we can ev aluate the propagation le ngths at air/silver interface are about 20 m and 500 m for = 500 nm and = 1 m, respectively. Surface Plasmon Excitation As seen above, light does not couple to the surface plasmon on metal surface due to no crossing point between the dispersion curves of the in cident light and the surface plasmon except for k = 0. There are two ways to exci te the surface plasmon optically on an interface of a dielectric a nd a metal. First, one can use a dielectric prism to make coupling between the incident photons and the surface plasmon on an interface between the prism and the metal [8]. But this is not a case which is studying in this dissertation, so

PAGE 28

15 I am going to skip this part. Second, one can use periodic structures on the metal surface. When light is incident on the grating surface, the incident light is scattered by the grating structure. The surface component of the scat tered light gets an additional “momentum” from the periodic grating structure. This additional momentum enables the surface component of the scattered light to exc ite the surface plasmon on metal surface. (a) (b) Figure 2-4. Schematic diagrams of (a) th e excitation of the surface plasmon by the incident photon on a metallic grating su rface and (b) the dispersion curves of the incident photon, the scattere d photon and the surface plasmon Incident photon sp k0 ksp =c k kx Scattered photon Surface plasmon z Photon, k0 Surface plasmon, ksp x A ir d a0 Metal m

PAGE 29

16 Let us consider this case for one dimensi onal grating, as shown in Figure 2-4 (a). When light with a wave number k 0 is incident on a periodic gating on a metal surface with an incident angle 0, the incident light excites the surface plasmon on the metal surface. The momentum conservation equation allows this surface plasmon to have a wave vector, ksp, equal to a sum of the x -component of the incident wave vector and an additional wave vector which is the Bragg ve ctor associated with the period of the structure: c k a m k ksp 0 0 0 0, 2 sin (2-40) where k0 is the wave number of the incident light, and a0 is the period of the grating structure, and m is an integer. As shown in Figure 2-4 (b), this additional wave vector shifts the dispersion line of the incident light to the disper sion line of the diffracted photon. This light line crosses the dispersion curve of the surface plasmon. This crossing means that the incident light couples with the surface plasmon on the metal grating surface. If we consider a two dimensional grati ng on the metal surface, as shown in Figure 2-5, the momentum conservation equation becomes 02 a j iy x y x y x sp g g g g k k k (2-41) where kx and ky are surface components of the incident wave vector, gx and gy are the Bragg vectors, a0 is a period of the grating, i and j are intergers. From Eqs. (2-24) and (241), we get an equation which predicts the re sonant coupling wavelengths of the incident light and the surface plasmon on me tallic grating surface. Putting sp xk k in Eq. (2-24), we get an equation:

PAGE 30

17 0 2 2 2 2 0 2 2 0sin ) ( sin j j i i j i am d m d sp (2-42) From this equation, one can predict the wave length where the incident light excites the surface plasmon on the meta llic grating surface. The surface plasmon excitation wavelength is used to explain the enhanced transmission phenomenon of the sub-wave length hole array because the excitation wavelengths are close to the wavelength of the enhanced transmission [7]. But the surface plasmon excitation wavelength shows a 15 % di fference between theoretical calculation and experimental measurement [9]. Mechanism of Transmission via Surface Plasmon Coupling in Periodic Hole Array As we mentioned, the surface plasmon is a collective excitation of the electrons at the interface between metal and insulator. This surface plasmon can couple to photons incident on the interface of meta l and insulator if there exists a periodic grating structure on the metal surface. So, the coupling between photon and surface plasmon forms the surface plasmon modes on the interface. If bot h sides of metal film have the same periodic structure, such as an array of holes, the surface plasmon modes on the input and exit sides couple and transfer energy from the input side to the exit side. The surface plasmon modes on the exit side decouple the photons for re-emission. In this optical transmission process, the energy transfer by the resonant coupling of surface plasmon on the two sides is a tunneling process through the sub-wavelength apertures. Thus, the intensity of transmitted light decays with a film thickness exponentially. To compensate this decay, a localized su rface plasmon (LSP) [43-46] plays a role in this process. The LSP is a dipole moment formed on the edges of a single aperture due

PAGE 31

18 Figure 2-5 Schematic diagrams of the excitati on of the surface plasmon by the incident photon on a two dimensional metallic grating surface Figure 2-6. Schematic diagram of transmis sion mechanism in a sub-wavelength hole array. (1) excitation of surface plasm on by the incident photon on the front surface (2) resonant coupling of surf ace plasmons of the front and back surfaces (3) re-emission of photon from surface plasmon on the back surface Photon SP m d a0 x y z Photon Photon SPinSPout(1) (2) (3) Metal

PAGE 32

19 to an electromagnetic field near the aperture and it depends mainly on the geometrical parameters of each hole. The LSP makes a very high electromagnetic field in the aperture and increases the probability of transmission of the incident light. CDEW (Composite Diffractive Evanescent Wave) A recently proposed theory competing w ith the surface plasmon theory is the CDEW [9, 47-49]. The CDEW is a second mo del explaining the enhanced transmission phenomenon of sub-wavelength periodic structures. Basic Picture of the CDEW The CDEW model originates from the scal ar near-field diffraction. Kowarz [50] has explained that an electr omagnetic wave diffracted by a two dimensional structure can be separated into two cont ributions: a radia tive (homogeneous) and an evanescent (inhomogeneous) contributions. The diffracted wa ve equation for the 2-D structure is based on the solution to the 2-D Helmoltz equation: 0 ) ( ) (2 2 z x E k (2-43) where 2 2 2 2 2y x 2 k and ) ( 0) (z k x k iz xe E z x E, the amplitude of the wave propagating in the x z directions. As mentioned, the diffracted wave is a sum of the radiative (homogeneous) and the evan escent (inhomogeneous) contributions: ) ( ) ( ) ( z x E z x E z x Eev ra (2-44) We note that the homogeneous and the evanes cent components separately satisfy the Helmoltz equation. If we consider that the incident plane wave with a wave vector k0 impinges on a single slit of width d in an opaque screen, as shown in Figure 2-7 (a), the momentum conservation of the incident wave an d the diffracted wave should satisfy

PAGE 33

20 2 2 0 x zk k k (2-45) where kx and kz are the wave vectors of the diffracted wave in the x and z directions. If kx is real and if 0k kx then 2 0 2k k i kx z (2-46) This result means that the diffractive wave propagates in the x direction while being confined and evanescent in z direction. This evanescent mode of the diffracted wave emerging from the aperture grows as d/ becomes smaller. In contrast, for 0k kx kz remains a real quantity and the light is diffr acted into a continuum of the radiative, homogeneous mode. In Figure 27, the diffraction by an apertu re is described in real space (a) and k -space (b). The blue lines re present the radiative modes (0k kx ), whereas the red lines represent the evanescent mode (0k kx ). The surface plasmon mode in this picture is the green line which is one of th e evanescent modes diffracted by the aperture. Now, in order to find the specific solutions for the radiative and evanescent modes, we need to solve Eq. (2-43). The solution for Eev at the z = 0 is 2 for 2 Si 2 Si ) 0 (0 0 0d x d x k d x k E x Eev (2-47) 2 for 2 Si 2 Si ) 0 (0 0 0d x d x k d x k E x Eev (2-48) where E0 is the amplitude of the incident plane wave and 0sin ) ( Si dt t t. If we consider the surface wave on the metal, Eq. (2-47) can be simplified with a good approximation as [9]

PAGE 34

21 ) 2 cos(0 0 x k x d E Eev (2-49) From the expression of CDEW in Eq. (2-49), we notice that the amplitude of the CDEW decreases as 1/ x with the lateral distance, x and its phase is shifted by /2 from the propagating wave at the center of the slit. These results are different from the surface plasmon. The phase of the surface plasmon is eq ual to that of the incident wave and its amplitude is constant if absorption is not c onsidered [9] Figure 2-8 shows the lateral field profile of CDEW. Figure 2-7 Geometry of optical scattering by a ho le in a real screen in (a) real space and (b) k-space for a range that kx is close to zero [9].

PAGE 35

22 Figure 2-8. CDEW lateral field profile at z = 0 boundary, a plot of Eq. (2-44) [47] CDEW for an Aperture with Periodic Corrugation So far we have been discussing the di ffraction by a single aperture. Now we are going to extend our discussion to the period ic corrugation around a single aperture as shown in Figure 2-9. The corrugations are on bo th input and output su rfaces and actually play a role as CDEW generating points. The individual corrugation also becomes a radiating source. As shown in Figure 2-9, when a plan e wave impinges on the periodically corrugated input surface with an aperture at the center, only a small part of the incident light is directly transmitted through the aperture. Of the rest part of incident light is directly reflected by the metal surface and part of the incident light is scattered by the corrugations. This scattering produces CDEWs on the input surface (red arrows). The CDEWs propagate on the input surface and are scattered by the corrugations. The

PAGE 36

23 corrugations on the input surface act as point sources for the scattered light which is radiating back to the space. Part of the CDEWs propagating on the input surface is scattered at the aperture and tr ansmitted to the output surfac e along with the light directly transmitted through the aperture. When the tr ansmitted light (directly transmitted light and CDEWs) arrives at the output surface, a sma ll part of the light ra diates directly into space and the rest of the light is scattered ag ain by the aperture and corrugations on the output surface. The output surface CDEWs ar e now produced by the scattering of the transmitted light and it propagates on the output surface between the aperture and the corrugations. These propagating CDEWs on the output surface are scattered again by the corrugations and radiated into the front space. This means that the each corrugation on the output surface also becomes a radiation source. Thus, the transmitted light can be observed from all over the corrugation structure at the near field. At the far field, the radiation from the corrugations and the transmitted light from the aperture are superposed and interfere with each other. As discussed before, the CDEW has /2-phase difference from the transmitted light. Therefore, the CDEWs and the directly transmitted light make an interference pattern. The interference patt ern of these two waves at the far field has been observed experimentally. [49] CDEW for a Periodic Sub-Wavelength Hole Array Now we are going to develop the CDEW model for a periodic array of subwavelength holes. The CDEW model for the peri odic hole array is similar to that of an aperture with periodic corrugations, excep t there are many holes rather than one. As shown in Figure 2-10, a plane wave is incident on the input surface of a periodic hole array. The incident wave is partiall y reflected, diffracted, and transmitted. The

PAGE 37

24 Figure 2-9.CDEW picture for an aperture with periodic corrugations on the input and output surfaces. Red arrows indicate the CDEWs generated on the input and output surfaces. Figure 2-10. A CDEW picture for a periodic sub-waveleng th hole array. Red arrows indicate the CDEWs generated on the input and output surfaces. Incident plane wave Reflected wave Scattered wave Scattered wave Transmitted wave CDEWs Incident plane wave Reflected wave Scattered wave Scattered wave Transmitted wave CDEWs

PAGE 38

25 reflected wave consists of a direct reflect ion by the metal surface a nd the back scattering from the hole, similar to the case of the hole with corrugations in the previous section. Like the corrugations in Figure 2-9, each hole acts as a point for scattering and radiation of the CDEWs on the input surface. The CDEWs on the input surface are partially scattered back to space and partially transm itted along with the dire ctly transmitted wave through the holes to the output surface. Thus, the transmitted wave is a superposition of the CDEW and the wave directly transm itted through the holes. When the transmitted light arrives at the output surface, it is partially scattered (generates CDEWs on the output surface) and partially radiated into space. The CDEWs generated on the output surface propagate on the surface, a nd are partially scattered and radiated into space. In the front space, the directly transmitted wave fr om the holes and the radiation from the CDEWs are superposed to be the total transm ission of the hole array for detection at the far field observation point. Fano Profile Analysis Genet et al. [13] proposed that the Fano line shape in transmittance of periodic subwavelength hole arrays is a st rong evidence of an interference between a resonant and a non-resonant processes. Figure 2-11 shows sc hematic diagrams for the coupling of the resonant and non-resonant processes in a hol e array. In Figure 2-11, the period of hole array is a0, the thickness is h and the hole radius is r As shown in this figure, there are two different scattering channels: one open channel 1 corresponding to the continuum of states and one closed channel 2 with a resonant state wh ich is coupled to the open channel with is called “direct” or “non-res onant” scattering proce ss. The other possible transition is that the input state transits to the resonant state (sometimes called quasibound state) of the closed channel and then couples to the open channel via the

PAGE 39

26 coupling term V This is called “resonant” scattering process meaning opposed to the first one. The “non-resonant” scattering process si mply means the direct scattering of the input wave by the sub-wavelength hole array. This scattering can be called Bethe’s contribution. Bethe’s contributi on is the direct transmission through the holes in the array which is proportional to ( d/)4 and will be detected as a background in transmttance. In contrast, the “resonant” scattering process is a contribution from the surface plasmon excitation. This resonant scattering process basically consists of two steps: (1) the excitation of the surface plasmon on the peri odic structure of metal surface by the input wave and (2) the scattering of the surface plasmon wave by the periodic structure. The surface plasmon wave can be scattered into free space (reflection) or into the holes in the array (transmission). A simple transmission di agram of this model can be described via Figure 2-12. The total transmission amplitude is decided with the interference of the nonresonant contribution (Bethe’s contributi on) and the resonant contribution (surface plasmon contribution). A paper published by Sarrazin et al. [12] has also discussed the Fano profile analysis and the interference of resonant a nd non-resonant processes. In Figure 2-13, the homogeneous input wave ( i ) incident on the diffraction element A is diffracted and generates a non-homogeneous resonant diffraction wave (e) which is characterized by the resonance wavelength, This resonant wave (e) is di ffracted by the diffraction element B and makes a contribution to the homogeneous zero diffraction order. On the other hand, the other input wave is inci dent on the diffraction element B and generates a non-resonant homogeneous zero diffraction order. This non-re sonant scattered wave from B interferes with the resonant wave of from A. The Fano profile in transmittance of the sub-

PAGE 40

27 wavelength hole array results from a superpos ition of the resonant and the non-resonant scattering processes. Figure 2-11. Schematic diagrams for Fano profil e analysis. (a) Formal representation of the Fano model for coupled channels and (b) physical picture of the scattering process through the hole array directly (straight arrows) or via SP excitation [13] Figure 2-12. A schematic diagram of th e non-resonant transmission (Bethe’s contribution) and the resonant transm ission (surface plasmon contribution) [14]

PAGE 41

28 Figure 2-13. Schematic diagram of the in terference between the resonant and nonresonant diffraction in transmission of sub-wavelength hole array [12]

PAGE 42

29 CHAPTER 3 INSTRUMENTATION Optical transmittance measurements have been taken using two spectrometers: a Perkin-Elmer 16U monochromatic spectro meter and a Bruker 113v fourier transform infrared (FTIR) spectrometer. The Perkin -Elmer 16U monochromatic spectrometer was used for the wavelength range from ultrav iolet (UV), throughout visible (VIS) and to near-infrared (NIR), i.e., between 0.25 m and 3.3 m. Measurement for longer wavelengths (> 2.5 m) employed the Br uker 113v FTIR spectrometer. The FTIR spectrometer is able to measure up to 500 m, but in this experiment it was used for a range between 2.5 m and 25 m, i.e., near-i nfrared (NIR) and mid-infrared (MIR). Perkin-Elmer 16U Monoch romatic Spectrometer A spectrometer is an apparatus designed to measure the distribution of radiation in a particular wavelength region. The Perk in-Elmer 16U monochromatic spectrometer consists of three principal parts; light s ource, monochromator a nd detector. Figure 3-1 shows a schematic diagram of the Perkin-Elmer 16U monochromatic spectrometer. Here, the spectrometer has three light sources, two detectors and a gating monochromator. Light Sources and Detectors This spectrometer has three different li ght sources installed: a tungsten lamp, a deuterium lamp and a glowbar. The tungsten lamp is for VIS and NIR (0.5 m ~ 3.3 m), and the deuterium lamp is for VIS and UV (0.2 m ~ 0.6 m). This spectrometer has the glowbar for MIR region, but it was not used because the matching detector for MIR region has not been installed. This monochrom atic spectrometer has two detectors: a lead

PAGE 43

30 sulfide (PbS) detector for VIS and NIR range (0.5 m ~ 3.3 m) and a Si photo conductive detector (Hamamatsu 576) for UV and VIS range (0.2 m ~ 0.6 m). Figure 3-1. Schematic diagram of Perkin-Elmer 16U monochromatic spectrometer Grating Monochromator A monochromator is an optical device that transmits a selectable narrow band of wavelengths of light chosen from a broa d range of wavelengths of input light.

PAGE 44

31 Monochromators usually use a pr ism or a grating as a dispersive element. In prism monochromators, the optical dispersion phenomenon of a pris m is used to separate spatially the wavelengths of light, whereas the optical diffraction phenomenon of grating is used in the grating monochromators for th e same purpose. In this section, only the grating monochromator will be discussed. Monochromator configuration There are several kinds of monochromator configurations. The configuration of monochromator which is used in Perkin -Elmer 16U spectrome ter is the Littrow configuration. A schematic diagram of the L ittrow configuration is shown in Figure 3-2. Figure 3-2. Schematic diagram of the Littro w configuration in the monochromator of Perkin-Elmer 16U spectrometer In this configuration, the broad-band light enters the monochromator through slit A, which is the entrance slit. This entrance sl it controls the amount of light which is available for measurement and the width of the source image. The light that enters through the entrance slit (slit A) is collimated by mirror A, which is a parabolic mirror. The collimated light is such that all of the rays are parallel and focused at infinity. The collimated light is diffracted from the grat ing and collected again by the parabolic mirror

PAGE 45

32 (mirror A) to be refocused. The light is then reflected by the plane mirror (mirror B), and sent to the exit slit (slit B). At the exit slit, the wavelengths of light are spread out and focus their own images of the entrance slit at different positions on the plane of exit slit. The light passing through the exit slit contai ns an image of the entrance slit with the selected wavelength and the part of the imag e with the nearby wavelengths. Rotation of the grating controls the wa velength of light which can pass through the exit slit. The widths of the entrance and exit slits can be simultaneously controlled to adjust the illumination strength. When the illumination st rength of the input light becomes stronger, the signal to noise (S/N) rati o becomes higher but, at the same time, the resolution of measurement becomes lower because the exit slit opens wider and passes a broader band of the light. Resolution of monochromator One of the important optical quantities of monochromator is its resolution. The resolution of monochromator in the Littrow configuration ( = = ) can be expressed as [51] ) 1 ( ) 1 ( 1g sR R R (3-1) f S Rs2 cot (3-2) ) (0h R Rg (3-3) where Rs is the resolving power contributed fr om optical quantities of all components except for the grating, Rg is the ultimate resolving power of the grating, S is the slit width, is the angle of incidence and diffraction, f is the focal length of collimating mirror, h ( )

PAGE 46

33 is an error function, and R0 is the resolving power of the grating. Thus, the resolution of monochromator is dependent not only on th e grating but also on other optical and geometrical quantities of the monochromator. The Diffraction Grating A diffraction grating is one of the dispersi ng elements which are used to spread out the broad band of light and spatia lly separate the wavelengths. Grating equation and diffraction orders Figure 3-3 shows the conventional diagram fo r a reflection grating. In this Figure, the general equation of grati ng can be expressed as [52] QR PQ difference Path m d d sin sin (3-4) where m is diffraction order which is 0, 1, 2 …. Figure 3-3. Schematic diagram of a reflection grating. If m becomes zero, the zero order diffr action. When the diffraction angle is on the left-side of the zero order angle, the diffraction orders are all positive, 0 m, whereas if the angle crosses over the zero order and is on the right side of the zero order, the diffraction order m becomes negative, 0 m.

PAGE 47

34 Blaze angle of the grating Most modern gratings have a saw-tooth pr ofile with one side longer than the other as shown in Figure 3-4. The angle made by a groove’s longer side and the plane of the grating is the blaze angle. The purpose of this blaze angle is so that, by controlling the blaze angle, the diffracted light is concentr ated to a specific region of the spectrum, increasing the efficiency of the grating. Figure 3-4. Schematic diagram of a blazed grating Resolving power of grating As mentioned before, the resolving power of a grating is one of the important optical quantities contributing in the resolution of monochrom ator. If we use the Rayleigh criterion, the resolving power of grating becomes sin sin W mN R (3-5) where N is the total number of grooves on the grating, W is the physical width of the grating, is the central wavelength of th e spectral line to be resolved, and are the angles of incidence and diffraction, respectiv ely. Consequently, th e resolving power of

PAGE 48

35 grating is dependent on the width of grating, the center wavelength to be resolved, and the geometry of the optical setup. Bruker 113v Fourier Transform Infrared (FTIR) Spectrometer As mentioned before, the Bruker 113v FT IR spectrometer was used to measure transmission in the range of MIR (2.5 m ~ 25 m). Basically, this FTIR spectrometer can cover up to the range of far-infrared (FIR) which is up to 500 m. The entire system is evacuated to avoid absorption of H2O and CO2 for all of the measurements. Interferometer The interferometer is th e most important part in FTIR spectrometer. The interferometer in a FTIR spectrometer is a Michelson interferometer with a movable mirror. The Michelson interferometer is shown in Figure 3-6. The electric field from the source can be expressed as x k ie E x E 0) ( (3-6) where x is a position vector, k is a wave vector and E0 is an amplitude of the electric field. As shown in Figure 3-6, l1, l2, l3 and l2+x /2 are the distances between the source and the beam splitter, the beam splitter and the fixed mirror, the beam splitter and the detector, and the beam splitter and the mova ble mirror, respectively. The reflection and transmission coefficients of the beam splitter are rb and tb, and the reflection coefficients and the phases of the fixed mirror and the movable mirror are rf, f and rm, m, respectively. The electric field Ed which arrives at the detector consists of two electric field components: one from the fixed mirror, Ef, and the other from the movable mirror, Em.

PAGE 49

36 Figure 3-5. Schematic diagram of Michelson interferometer Thus, Ed, Ef, and Em are m f dE E E (3-7) 3 2 2 10ikl b i ikl f ikl b ikl fe t e e r e r e E Ef (3-8) 3 2 2 1) 2 ( ) 2 ( 0 ikl b i x l ik m x l ik b ikl me r e e r e t e E Em (3-9) To simplify, consider the mirrors as perfect mirrors, so rf and rm are 1. Also, we define the frequency as follows 2 2c k (3-10) With c = 1, Eq. (3-10) becomes 2 and we measure x in cm and in cm-1. If we let f m ) (, ml l l k ) 2 (3 2 1 ) 1 ()) ( ( 0 x i i b b de e t r E E (3-11) The light intensity at the detector is

PAGE 50

37 ))] ( cos( 1 [ 20 x T R S E E Sb b d d d (3-12) where 0 0 0E E S Rb and Tb are the reflectance and the transmittance of the beam splitter. Sd is the intensity of light at th e detector for a given frequency Then the total intensity for all frequencies is 00 0))] ( cos( 1 [ 2 ) ( ) ( d x T R S d S x Ib b d d (3-13) For an ideal beam splitter, Tb = 1 Rb and RbTb with Rb = 1/2 is 4 1 ) 1 ( b b b bR R T R (3-14) Here we define the beam splitter efficiency, b, as follows ) 1 ( 4 4b b b b bR R T R (3-15) Then, Eq. (3-13) becomes d x S x Ib d 0 0))] ( cos( 1 )[ ( ) ( 2 1 ) ( (3-16) Here we have two special cases, x and x = 0. For x Id in Eq. (3-17) becomes Id ( ) called the average value: 0 0) ( ) ( 2 1 ) ( d S Ib d (3-17) With x = 0 and ( ) = 0 (zero path difference or ZPD), Id becomes Id (0) called the white light value: ) ( 2 ) ( ) ( ) 0 (0 0 d b dI d S I (3-18) Now we need to define another quantity whic h is the difference between the intensity at each point and the average value called the interferogram: d x S I x I xd d)) ( cos( ) ( 2 1 ) ( ) ( ) (0 (3-19)

PAGE 51

38 where S ( ) S0( ) b( ) and ( x ) is the cosine Fourier Transform of S ( ). If we assume that S ( ) is hermitian, then ( x ) is d e e S xx i i ) () ( 4 1 ) ( (3-20) and dx e x e Sx i i ) ( 2 ) () ( (3-21) From the measurement with the interf erometer, we get the interferogram, ( x ) and compute the Fourier transform to get the spectrum, S ( ). The resolution of a Fourier spectrometer consists of two term s: one contributed from the source and the collimation mirror a nd the other decided by the maximum path difference. 2 11 1 1 R R R (3-22) 2 2 18 h f R (3-23) l R2 (3-24) where f is the focal length of the collimating mirror, h is the diameter of the circular source, l is the maximum path differe nce or the scan length and is the wave number in cm-1. Description of FTIR Spectrometer System A simple description of interferometer of the FTIR spectrometer is as follows. The light from a source is focused on a beam splitter after reflected by a collimation mirror. This beam splitter divides th e input light into two beams: one reflected and the other transmitted. Both beams are collimated by two id entical spherical mirrors to be sent to a

PAGE 52

39 two-sided moving mirror. The moving mirror reflects both beams back to the beam splitter to be recombined and the recombined beam is sent to the sample chamber for measurement. Figure 3-6. Schematic diagram of the Bruker 113v FTIR spectrometer As shown in Figure 3-6, the Bruker 113v FTIR spectrometer consists of 4 main chambers: a source chamber, an interferometer chamber, a sample chamber and a detector chamber. In the source chamber, th ere are two light sources: a mercury arc lamp for FIR (500 m ~ 15 m) and a glowbar source for MIR (25 m ~ 2 m). The interferometer chamber has act ually two interferometers fo r a white light source and a helium-neon (He-Ne) laser. As we know the exact wavelength of the laser, the small interferometer with the He-Ne laser is used as a reference to mark the zero-crossings of its interference pattern which defines the positions where the interferogram is sampled. This is the process of digitization of interferogram.

PAGE 53

40 White light transmission and reflection are measured in the sample chamber. The transmission is measured in the front side of the sample chamber and the reflection is measured in the back. There are two detectors installed in the detect or chamber: a liquid helium cooled silicon bolometer and a r oom temperature pyroelectric deuterated triglycine sulfate (DTGS) detector. The bolom eter detects light signals in the FIR range (2 m ~ 20 m) and the DTGS detect or is for MIR (2 m ~ 25 m).

PAGE 54

41 CHAPTER 4 SAMPLE AND MEASUREMENT Sample Preparation The sub-wavelength periodic array sample s were prepared using electron-beam lithography and dry etching. Th e sample fabrication proce ss is simply described as follows. Silver films with thickness be tween 50 nm and 100 nm were deposited on substrates using thermal evaporation. Fused si lica and ZnSe were used for the substrates. Before the E-beam writing process, a PMMA film is coated on the silver film. The PMMA coated samples were baked on a hot plate at 180 C for a minute. The baked PMMA film was exposed by the electron beam to make a periodic pattern on it. After the E-beam writing, the sample developed with the area of the PMMA film, which was not exposed by the electron beam, removed by the developing solution. The patterned PMMA film is going to be used to mask the silver film from the dry etching. During the dry etching process, Ar-ions strike the surface of the sample to make holes on the silver film. Finally, the remaining PMMA mask wa s removed with the stripping solution. With this fabrication process, a variety of samples have been prepared for this research, listed in Table 4-1. SEM images of the selected samples are also shown in Figure 4-1. Substrates Fused silica and ZnSe were used for the substrates. When the enhanced transmittance is expected to occur at wavelengths shorter than 5000 nm, fused silica substrate is used. If the transmission peaks are supposed to occur at wavelengths longer

PAGE 55

42 (a) (b) (c) (d) (e) (f) Figure 4-1. SEM images of peri odic hole arrays samples. (a) A14-1, (b) A14-3, (c) A18-1, (d) A18-2, (e) A18-3, and (f) A18-4

PAGE 56

43 than 5000 nm, ZnSe substrate is used. It is because fused silica is transparent between 300 nm and 5000 nm, while ZnSe is transpar ent between 500 nm and 15000 nm [53]. Measurement Setup We have used the Perkin -Elmer 16U monochromatic spectrometer and Bruker 113v FTIR spectrometer for transmittance measurem ent. Transmittance of an open aperture and of the sample has been measured. We firs t measured an open ap erture as a reference and then measured the sample. We used the same diameter aperture when measuring the sample to keep the measurement area the same. Then we calculated the ratio of the transmission of the sample to that of the open aperture to get the transmittance of the sample. Table 4-1. List of the periodic sub-wavelength hole arrays sample hole shape hole size (nm) period (nm) film thickness (nm) A14-1 square 900 x 900 2000 70 A14-2 square 900 x 900 3000 70 A14-3 square donut 900 x 900(out) 500 x 500(in) 2000 70 A15 square 500 x 500 1000 50 A18-1 square 840 x 840 2000 100 A18-2 rectangular 900 x 1300 2000 100 A18-3 slit 1000 (width) 2000 100 A18-4 square on rectangular grid 900 x 900 2000 (x-axis) 1500 (y-axis) 100 We measured transmittance as a function of the angle of incidence. The samples were mounted on a transmission sample holde r that allows change s in the angle of incidence. A picture of the transmission sample holder is shown in Figure 4-2. By rotating about an axis perpendicular to the direction of the incident li ght, the angle of incidence is changed. We measured transmittance at every 2 degrees between 0 degrees and 20 degrees. Also, we have varied the in-plane azimuthal angle. The azimuthal angle can be

PAGE 57

44 varied from 0 degrees to 360 degrees. We used this measurement to study the effect of polarization direction. This a ngle can be controlled using the same transmission sample holder by rotating the sample mounti ng plate shown in Figure 4-2. Figure 4-2. Picture of the sample holder used to measure transmittance with changing the angle of incidence and the in-plane azimuthal angle After the exit slit of the monochromator of Perkin-Elmer 16U spectrometer, we could installed one of three diff erent polarizers. A wire grid po larizer that is made of gold wires deposited on a silver bromide substr ate is used for the MIR region, and two dichroic polarizers are used for NIR, VIS and UV regions. We can get the either spolarized or p-polarized inci dent light by using these polar izers. Another wire grid polarizer has been installed on the exit apertu re of the interferom eter chamber of the Bruker 113v FTIR spectrometer to get polari zed light in the MIR region. In the FTIR spectrometer, the polarizer is rotated instead of the sample. Incident angle rotator Azimuthal angle rotator Sample mounting plate (An open aperture at center)

PAGE 58

45 In the Perkin-Elmer spectrometer, an optical solid half angle of the incident light on samples is adjustable with an iris aperture installed on the spherical mirror before the transmission sample holder (see Figure 3-1), but for most of measurement, we set the iris aperture to make this angle 1 , to minimi ze the incident angle effect. The optical solid half angle of the Bruker 113v spectrometer is about 8.5 and was not adjusted. Once we measured the samples with both sp ectrometers, the two transmittance data have been merged into one transmittance data by our own data merging program.

PAGE 59

46 CHAPTER 5 EXPERIMENTAL RESULTS In this chapter, we present our experiment al results. These experimental results will be shown as follows. First, we present expe rimental data for the transmittance of the arrays of square holes. We discuss the depe ndence on the period of the hole arrays, and also on the thickness of the metal films. Sec ond, transmittance of the square hole array as a function of the angle of incidence usi ng polarized light is presented. Third, transmittance with different hole shapes, hole sizes and in-plane polarization angles are shown. Finally, transmittance with different di electric materials interfaced to the metal film is presented. Enhanced Optical Transmission of Sub-wavelength Periodic Hole Array Figure 5-1 shows the transmittance of s quare hole array (A14-1) between 300 nm and 5000 nm. As shown in this figure, the transmittance maximum occurs at 3070 nm which shows an intensity of 60 %. This is a bout 3 times greater than the fraction of open area. This means that the light which is impinging not only on the hole area but also on the metal surface transmits into the output surface of the hole array via a certain transmission mechanism. This enhanced tran smission of sub-wavelength hole array was first reported by Ebessen et al in 1998. [7] The reason why it is called “enhanced” is that the transmittance intensity is not only greater than the fraction of open area but also much greater than a prediction from the classical electromagnetic th eory for transmission of an isolated aperture proposed by Bethe in 1944 [2]. Other spectral features we see from this transmittance are the second highest peak at 2450 nm and another sharp peak at 323 nm.

PAGE 60

47 The sharp peak at 323 nm is the bulk plasmon peak of silver and this is an intrinsic property of the metal which is silver. Figure 5-1. Transmittance of the square hole array (A14-1) and a silver film Comparison of Enhanced Transmission with Classical Electromagnetic Theory For comparison we need to recall the Bethe’s transmittance for a single subwavelength hole, Eq. (2-4): T D kD D A 4 6 4 218 2 27 64 (2-4) In Figure 5-2, we show the transmittance ca lculated with Eq. (2-4) for wavelengths up to 5000 nm and compare with the transmittanc e measured with the square hole array. As shown in Figure 5-2, Bethe’s calculati on is reasonable for wa velengths longer than 2000 nm which is 2 times greater than the di mension of hole. For wavelengths shorter Silver film (thickness 50 nm) A14-1 (thickness 70 nm) Open fraction

PAGE 61

48 than 2000 nm, the calculated tran smittance increases very rapi dly and is not compatible with the measured transmittance. At 3070 nm the intensity of the transmittance maximum is 2.93, while the transmission amplitude of Bethe’s calculation at the same wavelength is 0.19. Thus, the measured transmittance is 15 times greater th an the calculated one at the wavelength of the transmittance maximum. Figure 5-2. Comparison between Bethe’s ca lculation and the transmittance measured with the square hole array (A14-1) Dependence of Period, Film Thickne ss and Substrate on Transmission The experimental data shows that the enhanced transmission of sub-wavelength hole array depends on materials a nd geometrical parameters of sa mple. In this section, we discuss the dependence on the period of th e hole array, the film thickness and the substrate material on transmission.

PAGE 62

49 Dependence on Period of Hole Array For this experiment we prepared two di fferent hole array samples which have different periods of 1 m and 2 m, respectiv ely. These samples are fabricated on silver film. The thicknesses are 50 nm for the 1 m period sample and 100 nm for the 2 m period sample. The hole size for the 2 m period sample is 1 m 1 m and that of the 1 m period sample is 0.5 m 0.5 m. Both samples are prepared on fused silica substrates. Figure 5-3. Transmittance of square hole arra ys with periods of 1 m (A15) and 2 m (A18-1) Figure 5-3 shows the transmittance of both samples. The transmittance maxima for 1 m and 2 m period samples appear at 1560 nm and 2940 nm, respectively. The ratio of the two peak positions is about 1.88. This is very close to 2 which is the ratio of the periods of both samples. The second highe st peaks are located at 1170 nm and 2180 nm.

PAGE 63

50 The ratio of the second highest peak positions of both samples is 1.86 and it is almost the same with that of the maximum peak positions. The transmittance minimum or the dip more closely follows the ratio of the periods The dip located between two highest peaks occurs at = 1410 nm for the 1000 nm period sample and at = 2800 nm for the 2000 nm period sample. The ratio of dip positions is 1.98, almost same as the ratio of the periods of the two samples. From this simple consideration we are able to predict that the positions of peaks and dips in transmittance of sub-wavelength periodic hole arrays are closely associated with the periods of hole arrays. Dependence on the Thickness of Metal Film Another feature in Figure 5-3 is th e dependence of the transmittance on the thickness of the metal film. As indicated in this figure, the thickness of the metal film in the 1 m period array sample is 50 nm and th at of the 2 m period array sample is 100 nm. Two transmittances from these hole arrays show different spectral behaviors. The transmittance of the hole array with 50 nm thickness shows a stronger maximum peak, a higher background, and a broader line-width co mpared to the transmittance of the hole array with 100 nm thickness [55]. For a direct comparison between these hole array samples, we rescaled the x -axis to wavelength divided by the period of each array. These rescal ed transmittances are shown in Figure 5-4. The background in the transmittance for the hole array with 1 m period is higher than that of the hole array with 2 m period, due to the difference of thickness in the metal film. For a thinner metal film, transm ission through leakage paths in the film or direct transmission through meta l film increase. These kinds of contribution decrease when the thickness of film increases. Thus, the background for the ho le array with 2 m

PAGE 64

51 period decreases. The difference between the backgrounds of the 1 m period hole array and the 2 m period hole array is about 10 %. Figure 5-4. Transmittance vs. scaling variable, s = /( nd period), for the square hole arrays of 1 m period (A15) and 2 m period (A18-1) made on fused silica substrates ( nd = 1.4) From Figure 5-4, we can see a shift of the transmittance maximum even though these hole arrays are supposed to have the maximum at the same position in the rescaled x -axis. And also the positions of the dips in the transmittance of 1 and 2 m period hole arrays do not coincide but are slightly differe nt. This difference in position of peak or dip might be attributed to an imperfection in the geometrical structure of the hole arrays. But, if we take a closer look in th e figure, the peak of the 1 m period array has a little broader line-width than that of the 2 m period a rray. The broadness of transmission peak is basically coming from factors su ch as a larger hole size and a thinner film which increase

PAGE 65

52 the coupling strength between front and b ack surfaces. This coupling also probably causes the shift in peak position. Dependence on the Substrate Material The transmittance of the hole arrays depe nds on the dielectric materials interfaced with the hole array. In particularly, the posit ions of peaks and dips are strongly dependent on the dielectric material. In order to see the effect of the dielectric material in transmittance, we used two different substrates: fused silica and ZnSe. The dielectric constants of fused silica and ZnSe are 2.0 and 6.0, and the transmittances of bare substrates are 90 % and 70 %, respectively [53]. Figure 5-5 shows the transmittance of a 2 m period square hole array (A14-1) on different substrates: one on a fused silica substrate and the other on a ZnSe substrate. Even though those samples are on different s ubstrates, the film thickness of films was 70 nm for both transmittances. In Figure 5-5 (a), the hole array on fused silica has its transmittance maximum at 3070 nm while the maximum for the array on ZnSe substrate is at 5180 nm. The ratio of the peak positions of the two samples is about 1.69. We know the refractive indices of fused silica and ZnSe which are 1.4 and 2.4, respectively, so that nZnSe / nSiO2 = 1.7, close to the ratio of the peak wa velengths. This result indicates that the most dominant factor for this big red shift in the peak positions of these two hole arrays is the refractive index of the substrat e material. In Figure 5-5 (b), the x -axis is rescaled with wavelength divided by a product of th e refractive index and the period, s = / ( nd period). Even though the effect of the period a nd the refractive index is eliminated by the rescaling, the dip posi tions are still different between the two spectra. This is probably due to imperfections of the samples such as a difference in the thickness or the period.

PAGE 66

53 Figure 5-5. (a) Transmittance vs. wavelengt h (b) transmittance vs. scaling variable, s = /( nd period), for the square hole arrays of 2 m period (A14-1) made on a fused silica substrate ( nd = 1.4) and a ZnSe substrate ( nd = 2.4) (a) (b)

PAGE 67

54 Dependence on the Angle of Incidence In this section, we will discuss the effect of the incident angle on the transmittance. For this measurement we used the square hole array with 2 m period (A14). As mentioned in chapter 4, the incident a ngle is changed by rotating about an axis perpendicular to the incident light and the pl ane of incidence. For this measurement we used polarizers to get the sand p-polarized in cident light. We also measured with nearly unpolarized light. The transmittance was measured every 2 from 0 to 20 Figure 5-6. Transmittance of a square hol e array (A14-1) with three different polarizations at normal incidence From this experiment, we found a very strong dependence of the transmittance on the incident angle. In additi on, a significant polarization dependence of the transmittance at non-normal angle of incidence is also obser ved. The spectral behavior of transmittance of s and p-polarized light differ when the incident angle is changed [14, 56, 57].

PAGE 68

55 Figure 5-6 shows the normal incidence transmittance of a square hole array (A14-1) for three different polarizations. These spectra are almost the same except for the second highest peak. The intensity of the second peak for the case of unpolarization is a little higher than the peaks of others. A reason of this similarity in transmittance at normal incidence is that the sample (A14-1) used in this experiment has a geometrical symmetry for the two orthogonal polarizations. Figure 5-7 (a) shows schematically the s-pol arized light incident on a hole array sample. The lower panel, Figure 5-7 (b) shows the transmittance of a square hole array (A14-1) with s-polarized inci dent light as a function of the incident angle. The spolarization (TE mode) has a tran sverse electric field which is perpendicular to the plane of incidence. The magnetic field is in the plane of incidence. Fi gure 2-2 in Chapter 2 shows a schematic diagram for s-polarization. In Figure 5-7 (b), we can see some dependence on the transmittance on the angle of incidence. The intensity of the maximum tran smission peak decrease s and the line-width of the peak increases when the incident angle increases. The locations of both the maximum peak and of the dip shift to shorter wavelengths with increasing incident angle, while the second highest peak sh ifts the longer wavelengths. Figure 5-8 (a) shows a schematic diagram of p-polarized light incident on a hole array. Figure 5-8 (b) shows the transmittance of the same square hole array using ppolarized incident light as a function of the incident angle. The p-polarization (TM mode) has a transverse magnetic field, perpendicular to the plane of inciden ce. The electric field is in the plane of incidence. Figure 2-1 in Chapter 2 show s schematically the case of ppolarization. For p-polarization, the transmitta nce is quite different from that of the s-

PAGE 69

56 polarization as the incident angle changes. The maximum peak at 3070 nm at normal incidence splits into two peaks. One peak shifts to the longer wavelengths while the other peak shifts to the shorter wavelengths with increasing incident angle. (a) (b) Figure 5-7. Measurement of transmittance with s-polarized incident light as a function of the incident angle. (a) Schematic diag ram of s-polarized light incident on a hole array and (b) transmittance of a square hole array (A14-1) 0 k H E

PAGE 70

57 (a) (b) Figure 5-8. Measurement of transmittance with p-polarized incident light as a function of the incident angle. (a) Schematic diagra m of p-polarized light incident on a hole array and (b) transmittance of a square hole array (A14-1) The dip at 2860 nm also shows the same sp ectral behavior when the incident angle increases, splitting into two di ps, one of which shifts to s horter wavelengths and the other dip shifts to longer wavelengths with increasing incident angle. 0 k E H

PAGE 71

58 We cannot easily distinguish how the sec ond highest peak at 2450 nm changes. It is a very interesting feature that the transm ittance of the sand p-polarizations behave very differently as a function of the angle of incidence. Dependence on Hole Shape In this section, we discuss dependence of the transmittance on the hole shape and the in-plane azimuthal angle of polarization. For this measur ement, we prepared four hole array samples which have different shapes a nd sizes of holes. Those arrays are shown in Figure 4-1. The four sample s are: 1) an array of square holes with 1000 nm 1000 nm hole size and 2000 nm period (A18-1), 2) an array of rectangular holes with 1000 nm 1500 nm hole size and 2000 nm period (A18-2), 3) an array of slits with 1000 nm width and 2000 nm period (A18-3) and 4) an array of square holes on rect angular grid with 1000 nm 1000 nm hole size and 1500 nm period for x -axis direction and 2000 nm period for y -axis direction (A18-4). Square Hole Arrays Figure 5-9 shows the transmittance of the square hole array as a function of polarization angle. The spectra at all polarization angles (0 45 90 ) are the same. The transmittance maximum occurs at 2940 nm with an intensity of 60% for all three polarization angles. The behaviors at 0 and 90 polarization angles are due to geometrical symmetry of the square hole array. For 45 polarization angle, the electric field has decomposed into 0 and 90 components, making the spectra at 0 and 90 polarization angles to be the same. The transmittance peak at 2940 nm shows Fano line-shape which we discussed in Chapter 2. This Fano line-shape is a typical feature of the enhanced transmission of sub-

PAGE 72

59 wavelength hole arrays even though it is still not clear if it is due to the superposition of contributions from the resonant and non-re sonant scattering processes in transmission mechanism. Figure 5-9. Transmittance of square hole array (A18-1) as a function of polarization angle. The inset shows a SEM image of the square hole array. Rectangular Hole Array The transmittance of the rectangular hol e array for polarization angles of 0 and 90 are shown in Figure 5-10. As shown in the fi gure, it is evident that the transmission of the 0 polarization angle is very di fferent from that of the 90 polarization angle. For the 90 polarization angle, the transmitta nce maximum has an intensity of 83 % at 3300 nm. This peak disappears for 0 polarization angle while another peak appears at 2900 nm which shows an intens ity of 43 %. This difference between the 0o 45o 90o

PAGE 73

60 transmittance of 0 and 90 polarization angles shows th at the position of maximum transmittance strongly depends on polarization angle due to the asymmetry of rectangular holes. Figure 5-10. Transmittance of a rectangular ho le array (A18-2) for in-plane polarization angles of 0 and 90 The inset shows a SEM imag e of the rectangular hole array. Another interesting difference between the transmittance of 0 and 90 polarization angles is the lin e-width of the maximum peak Figure 5-10 shows that the line-width of the maximum peak in the transmittance of the 90 polarization angle is much broader that that of the 0 polarization angle. There is the second highest peak around 2300 nm in the transmittance spectra of 0 and 90 polarization angles. These peaks are locat ed at the same position with a similar 90o0o

PAGE 74

61 line-width. This is a different spectral beha vior compared to the large peaks at 2900 nm and 3300 nm. Figure 5-11. Transmittance of a slit array (A18-3) for in-plane polarization angles of 0 and 90 The inset shows a SEM image of the slit array. Slit Arrays The transmittances of the slit array for 0 and 90 polarization angles are shown in Figure 5-11, along with a SEM pictur e of the array (inset). The 0 polarization direction is parallel to the slit direction and the 90 polarization is perpendicular to the slit direction. The transmittance at 90 polarization angle shows a very broad transmittance peak around 4000 nm with an intensity of 73 %. This peak disappears for 0 polarization angle. This transmittance behavior of slit arra y is expected as slit arrays are used as a wire grid polarizer [52]. 90o0o

PAGE 75

62 The transmittance of the s lit array also shows a second maximum peak for both 0 and 90 polarizations around 2300 nm which is th e same position as the square and the rectangular hole arrays. But, in the transmittance of the 0 polarization angle, we hardly recognize the dips which exist in the transmittance of the 90 polarization angle at 2000 nm and 2800 nm. This is probably due to an ab sence of periodic grating structure in the direction of 0 polarization angle. Figure 5-12. Transmittance of a square hole array on a rectangular grid (A18-4) for polarization angles of 0 45 and 90 The inset shows a SEM image of the square hole array in a rectangular grid. Transmission of Square Hole Array on Rectangular Grid In order to see the effect of different periods in two orthogona l polarization angles, we prepared a square hole array on a recta ngular grid (A18-4). As mentioned previously, the periods in the 0 and 90 polarization angles are 1500 m and 2000 m, respectively.

PAGE 76

63 The hole size is 1000 nm 1000 nm which is the same as that of the square hole array (A18-1). Figure 5-12 shows the transmittance of the square hole array on a rectangular grid for 0 45 and 90 polarization angles. The transmittance at the 90 polarization shows a sharp maximum peak at 3020 nm and a second maximum at 2270 nm. The peak at 3020 nm disappears for the transmittance of the 0 polarization angle. Bu t the peak at 2270 nm remains at the same position with a little higher intensity for the 0 polarization angle. There is a small peak at 3000 nm in the spectrum of the 0 polarization angle and this might be due to a misalignment of polarization at the angle of 0 Refractive Index Symmetry of Dielectric Materials Interfaced with Hole Array Most of the samples that we have prepared are asymmetric structures with a fused silica substrate (or ZnSe substrate)/a periodic array on sliver film/air, as shown in Figure 5-13 (a). But there were some reports proposed an increase of the transmittance when sample has refractive index symmetry of diel ectric materials on both sides of hole array [58] In order to test an effect from this refractive index symmetry we used photo resist (Microposit S1800, Shipley) and PMMA (N anoPMMA, MicroChem) as a dielectric material to make the refractive index symmetr y with fused silica substrate. The refractive indices of PR and PMMA are approximately 1.6 and 1.5, respectively [59, 60], and the refractive index of fused silica is about 1.4 [42]. First, we measured transmittance of an original sample which is the square hole array (A14-1). Then, we coated PR or PMMA with a thickness of 150 nm on the top of hole array and measured the transmittance. Figure 5-13 shows schematic diagrams of each step of the sample preparation for measurement.

PAGE 77

64 Figure 5-14 and Figure 5-15 show the transmittance of square hole arrays on fused silica substrate and ZnSe substrate, and the sa me hole arrays with PR coated on the top. When the PR ( n 1.6) is coated on the hole arrays, the transmittance maximum of the hole array on fused silica substrate shifts more than 600 nm to longer wavelengths while the peak of the hole array on ZnSe substrate shifts only 60 nm which is small compared to that of the hole array on fused silica subs trate. There is a small increase in the peak intensity for the hole array on ZnSe substrate but there is almost no increase for the hole array on fused silica substrate. The dip at 2800 nm also shifts about 100 nm to longer wavelengths in the hole array on fused silica su bstrate but the same di p of ZnSe substrate sample shifts to longer wavelengths slightly. In addition, we used PMMA ( n 1.5) for this index symmetry experiment. As we know, the refractive index of PMMA is almost same as the refractive index of fused silica. Figure 5-16 shows transmission spectra of the square hole arra y (A14-1) with and without PMMA on top of the hole array. Th e transmittance of PMMA coated hole array shows the maximum transmittance at 3210 nm. This peak is shifted about 200 nm to longer wavelengths from 3010 nm where the maximum transmittance of the hole array without PMMA coating occurs. Another transmittance in Figu re 5-16 is measured with the same hole array but with another fused s ilica substrate attached on the top of PMMA. The transmittance with the second fused silica substrate shows no shift in the positions of peak and dip but a small decrease in transm ittance intensity compared to the spectrum of the PMMA coated hole array. The transmitta nce decrease is probably due to reflection and absorption by the additional fused silica substrate attached on the top of PMMA.

PAGE 78

65 Figure 5-13. Schematic diagram of sample prep aration (a) an origin al square hole array (b) a PR (or PMMA) coated square hole array (c) another fused silica substrate attached on top of PR (or PMMA) Figure 5-14. Transmittance of a square hole a rray (A14-1) on fused silica substrate with and without PR coated on the top Fused silica ( 1mm ) Ag pattern (100 nm) Fused silica Fusedsilica Photo resist or PMMA (150nm) Fused silica (a) (b) (c)

PAGE 79

66 Figure 5-15. Transmittance of a square hole array (A14-1) on ZnSe substrate with and without PR coated on the top of hole array Figure 5-16. Transmittance of a square hole a rray (A14-1) on fused silica substrate with and without PMMA coated on the top of hole array with the second fused silica substrate attached on the top of PMMA. Square hole array on Ag/fused silica glass (quartz)

PAGE 80

67 Even though we expected a remarkable in crease of the transmittance in the case of the fused silica substrate samples, it is hard to observe an increase in the measured transmittance. But this result shows that the peak and the dip of the hole array on fused silica substrate shift a lot more than the hole array on ZnSe substrate. It means that the spectral shifts of peak and dip by an addition of the inde x symmetry layer depend on the substrate material of the hole array.

PAGE 81

68 CHAPTER 6 ANALYSIS AND DISCUSSION In Chapter 5, we have shown the transmittance of various structures of hole arrays, which have different geometrical parameters (period, film thickness, incident angle and hole size) and the refractive indices of dielectric material. In this chapter, we will analyze and discuss a few important feat ures. First, we compute the theoretical predictions for the positions of peaks and dips, and compare them with experimental data. Second, we discuss the transmittance dependence on incident angle for sand p-polarized light. Third, we discuss the dependence on hole shape and size. Prediction of Positions of Transmission Peaks We need to recall one of surface plasmon equations which predicts the position of resonant transmittance peaks in two dimensional hole array. 0 2 2 2 2 0 2 2 0sin ) ( sin j j i i j i am d m d sp for non-normal incidence ( 0 0) (2-42) 2 1 2 2 0 m d m d spj i a for normal incidence ( 0 = 0) (6-1) With this equation, we can calculate wavelengths of the surface plamon resonant transmission peaks of a two dimensional hole array. For this calculation, we need the dielectric constants of air, subs trate materials and metal which is silver in this work. First, we know that the dielectric constant of air is 1. The substrate we mostly used is fused silica glass substrate. The diel ectric constant of fused silica glass is 2.0 for a wavelength

PAGE 82

69 range between 2000 nm and 3000 nm. We also need to calculate the di electric constant of silver. Generally, the dielectri c constant of a metal is a st rong function of frequency (or wavelength) and has a complex form: mi mr mi (6-2) where mr and mi are real and imaginary parts of m. mi is mainly associated with absorption of metal. m in Eqs. (2-42) and (6-1) is usually considered as the real part of dielectric constant of metal, mr. For calculation of m in Eq. (6-1), we consider silv er as an ideal metal and use the Drude model for free electrons. Eq. (2-35) gi ves the dielectric function of a Drude metal: 2 2 2 21 1p p m (2-35) where p is the bulk plasma wa velength of the metal ( p is the bulk plasma frequency). We use 324 nm for the bulk plasma wavelengt h, as measured in this experiment. From calculation of the dielectric constant of silver, we found that Ag for = 3000 nm is about –84.75 (and Ag = –49.71 for = 2000 nm). With these numbers, we get the wavelengths of the resonant transmittance p eaks for hole arrays with a period of 2 m using Eq. (6-1). The result of cal culation is shown in Table 6-1. Table 6-1. Calculated positions of surface pl asmon resonant transmittance peaks for three interfaces of 2000 nm period hole arrays at normal incidence ( d of air, fused silica and ZnSe are 1.0, 2.0 and 6.0, respectively) ( i, j ) air / metal interface fused silica / metal interface ZnSe / metal interface (0, 1) and ( 1, 0) 2020 nm (P2) 2860 nm (P1) 5080 nm (P4) ( 1, 1) 1450 nm (P3) 2040 nm (P2) 3590 nm (P5)

PAGE 83

70Comparison of Calculated and Measured Positions of Transmittance Peaks and Dips Figure 6-1 indicates the calculated positio ns of the transmittance peaks in the measured transmittance of a square hole array made on a fused silica substrate (A18-1). As shown in this figure, the calculated positions of the peaks do not match accurately with the peak positions in the measured transmittance. The difference between P1 and the maximum peak position in the measured transmittance is about 80 nm. The spectral difference for the second highest peaks is 140 nm. Even though many people still believe in the role of surface plasmon in the e nhanced transmission of sub-wavelength hole arrays, the discrepancy between the peak pos itions calculated with Eq. (6-1) and the measured peak positions still remains as an unsolved problem. Figure 6-1. Comparison of calculated peak pos itions with measured transmittance data. Transmittance measured with a square hole array (A18-1) is shown. P1, P2 and P3 are the calculated positions of three transmittance peaks. P1 P2 P3

PAGE 84

71 Actually, the surface plasmon equation, Eq. (2-42) (or, Eq. (6-1) for normal incidence), has some approximati ons that are not applicable to real systems. First, the dispersion relation of surface plasmon which is used to derive Eq. (2-42) is not for a system of periodic hole array structure but fo r a plane interface of metal and dielectric those are infinitely thick. This will give a difference in the dielectric constant of the system. Second, the surface plasmon e quation is based on the long wavelength approximation. Thus, it does not depend on the shapes and the sizes of holes, but it depends only on the periods of hole arrays. Th ird, as we mentioned in Chapter 2, the surface plasmon equation is derived for a system with an infinitely thick metal which is not possible in a real system. As the metal film is infinitely thick, it does not consider the effect from an interaction between two interfaces. But, in a real system, the thickness of metal film is finite, so there must be the interaction between two interfaces. Furthermore, if there are holes in the metal film, the inte raction will be stronger. These approximations could be a reason for the difference between the calculated and the measured peak positions. Another interesting feature is the dips in the transmittance. It is known that the transmittance minima of sub-wavelength hole arrays are due to Wood’s anomaly. According to Wood’s anomaly, the minima (dips) appear at wavelengths where the incident light is diffracted into the surface di rection by periodic gra ting structures, and the transmittance becomes a minimum. Eq. (6-2) is the diffraction equation of one dimensional grating for normal incidence [52]. sind nn d (6-3)

PAGE 85

72 where d is the groove spacing, n is an integer, d is the dielectric cons tant of the dielectric material and is the diffraction angle. As Wood’ s anomaly happens at the diffraction angle = 90 so there is no transmitted light at the wavelength: d nn d (6-4) If we consider two dimensional grati ng structure such as a hole array, n in Eq. (6-4) is replaced by 2 2j i and the equation becomes dj i a 2 2 (6-5) where i and j are integers and a is the period of two dimensional hole array. Eq. (6-5) is very similar with the surface plasmon equati on, Eq. (6-1), except for the dielectric constant. Because the dielectric constant of the metal is much bigger than that of dielectric material, the peak positions predic ted by Eq. (6-1) is very close to the dip positions predicted by Eq. (6-5). Table 6-2. Calculated positions of transmitta nce dips for three interfaces of 2 m period hole arrays at normal incidence (d of air, fused silica and ZnSe are 1.0, 2.0 and 6.0, respectively) ( i, j ) air / metal interface fused silica / metal interface ZnSe / metal interface (0, 1) and (1, 0) 2000 nm (D2) 2800 nm (D1) 4900 nm (D4) (1, 1) 1430 nm (D3) 2000 nm (D2) 3460 nm (D5) Table 6-2 shows the calculated positions of dips. Figure 6-2 shows the same transmittance shown in Figure 6-1 with the positi ons of the dips indicated. As we can see in Figure 6-2, the calculated positions of the dips coincide well with the positions of the dips in the measured transmittance. This is different from the discrepancy of the peak

PAGE 86

73 positions. The reasons why the positions of transmittance minima are matched better than the transmittance maxima are: 1) the diffracti on grating equation is derived for a periodic structure, not for a plane surface as the surface plasmon equation, 2) the diffraction grating equation is not dependent on the refractive index of th e grating material (metal), but only depends on the refractive index of th e dielectric material. Figure 6-3 shows the positions of the peaks and the dips for the ZnSe-metal interface with the measured transmittance of a square hole array (A14-1) made on a ZnSe substrate. This comparison between the calculation and the measurement for a hole array on a ZnSe substrate also shows a discrepancy in the peak positions and a good coincidence in the dip positions. Figure 6-2. Comparison of the calculated transmittance peaks and dips with the transmittance measured with a square hole array (A18-1) made on a fused silica substrate. P1, P2 and P3 are the calculated positions of the first three peaks and D1, D2 and D3 are the calculated positions of the first three dips. P1 P2 D2 D1 P3 D3

PAGE 87

74 Figure 6-3. Comparison of the calculated transmittance peaks and dips with the transmittance measured with a square hole array (A14-1) made on a ZnSe substrate. P4 and P5 are the calculated peak positions and D4 and D5 are the calculated dip positions for the ZnSe-metal interface. P2, P3, D2 and D3 are the positions of the peaks and the dips for the air-metal interface. Dependence of the Angle of Incidence on Transmission Fig. 6-4 shows the transmittance of an array of square holes (A14-1) on a silver film. This transmittance was measured using unpolarized light at normal incidence. As discussed before, the peak A and the dip B are attributed to (i, j) = (1, 0) or (0, 1) modes on the fused silica-metal interface, and they don’t vary with changing the polarization direction of the incide nt light at normal incidence. In the previous chapter, we have seen that the transmittance varies with the angle of incidence and also strongly depends on the polarization of the incident light. P4 P5 D5 D4 P2 D2 P3 D3

PAGE 88

75 In order to explain the spectral behavior of transmittance maximum on the angle of incidence, we need to reca ll the surface plasmon equation, Eq. (2-42). Even though the surface plasmon equation has some drawbacks in its approximation, it is still useful to explain the spectral behavior on the angle of incidence qualitatively. The surface plasmon equation for oblique incidence was already introduced in Eq. (2-42) of Chapter 2, and here we derive Eq. (2-42) us ing Eqs. (2-24) and (2-41): m d m d spc k Dispersion relation of surface plasmon (2-18) 02 ,a j iy x y x y x sp g g g g k k k (2-34) Figure 6-4. Transmittance of a square hole array (A14-1) measured using unpolarized light at normal incidence. A ( 1,0)Q, (0,1)Q B ( 1,0)Q, (0, 1)Q

PAGE 89

76 Figure 6-5. Schematic diagram of an excita tion of surface plasmon by the incident light on two dimensional metallic grating su rface. An azimuthal angle of the incident light is 0 so that the wave vector of the incident light is always on the plane of incidence and on the x-axis. As we did in Chapter 2, we set th e in-plane azimuthal angle to be 0 so that the incident light is on the x-z plane which is the plane of incidence. This is shown in Figure 6-4. The magnitude of kx in oblique incidence with 0 is k0 sin0 and 0 yk Therefore, the magnitude of ksp is 2 1 2 0 2 0 0 02 2 sin a j a i k ksp (6-6) From Eq. (6-6) and Eq. (2-24), we get an equation as 2 1 2 0 2 0 0 02 2 sin a j a i k cm d m d (6-7) m d a0 x y z Photon SP Plane of incidence

PAGE 90

77 (a) (b) Figure 6-6. Transmittance with s-polarized incident light. (a) Schematic diagram of (0, 1) and (0, -1) modes excited on a square hole array for s-polarization and (b) transmittance of a square hole array (A141) as a function of incident angle for s-polarization. The peak A and the dip B are attributed to (0, 1) and (0, -1) modes on the fused silica-metal interface that are degenerated in the spolarization case.

PAGE 91

78 (a) (b) Figure 6-7. Transmittance with s-polarized incident light. (a) Schematic diagram of (1, 0) and (-1, 0) modes excited on a square hole array for p-polarization and (b) transmittance of a square hole array (A14-1) as a function of the incident angle for s-polarization. The peak A and the dip B are attributed to (1, 0) and (-1, 0) modes on the fused silica-meta l interface that are separated with changing the angle of incidence in the p-polarization case.

PAGE 92

79 (a) (b) Figure 6-8. Peak and dip position vs. incident angle for s-polarization. (a) Peak position and (b) dip position. The red and the bl ue squares indicate the measured and the calculated positions, respectively.

PAGE 93

80 (a) (b) Figure 6-9. Peak and dip position vs. incident angle for p-polarization. (a) Peak position vs. incident angle and (b) dip positions vs. incident angle for p-polarization. The red and the blue squares indicate the measured and the calculated positions, respectively.

PAGE 94

81 With some steps of calculation and c c k 20 where is the wavelength of the incident light, we get Eq. (2-42) for the posit ion of resonant peak at oblique incidence: 0 2 2 2 2 0 2 2 0sin ) ( sin j j i i j i am d m d sp (2-42) For s-polarization case, the elect ric field of incident light is parallel to the rotating axis which is y-axis, so that only (0, j ) modes are excited. This means that the modes responsible for the transmittance maximum in th e s-polarization case are (0, 1) and (0, -1) mode on the fused silica-metal interfa ce. This is shown in Figure 6-6. From Eq. (2-42) we not ice that there are only j 2 terms, which means that the (0, 1) and (0, -1) modes on fused silica-met al interface are degenerate in j 2. This is the reason why there is no splitting in the peak A with changing the angle of incidence in the spolarization case. On the other hand, for the p-polarization case, the electric field of the incident light has two components which are parallel to the x -axis and the z -axis, but there is no y -axis component. The x -axis component of electric field allows only ( i 0) modes to be excited on the metal surface. Therefore, the peak A in th e p-polarization case is attributed to (1, 0) and (-1, 0) modes on the fused silica-metal interface. These modes are governed by a linear term of i in the Eq. (2-42) which is 0sin i By this term, the (1, 0) and (-1, 0) modes are separated with changing the angle of incidence, which shows a splitting of the peak A in the transmittance. In addition, in Figure 6-6 (b) and Figur e 6-7 (b), there is the dip B at 2860 m for normal incidence. The dip B shows the same spectral behavior as the peak A. As discussed before, this dip has been known as the Wood’s anomaly. Eq. (6-5) is an

PAGE 95

82 equation for the positions of the transmittance dips for normal incidence. If we consider oblique incidence, the momentum conservation equation is the same with Eq. (2-34). But the dispersion equation is different from the case of the transmittance peaks. The dispersion equation for the diff racted (grazing) light is dc k (6-8) Combining with Eq. (2-34) and a few st eps of calculation give the positions of transmission dips: 0 2 2 2 2 0 2 2 0sin ) ( sin j j i i j i ad dip (6-9) As we see from this equation, the position of the transmittance dip is also dependent on the angle of incidence, which is same as the transmittance peak. This is the reason why the dip B also shows the same spectral behavior as the peak A. Figures (6-8) and (6-9) show the positions of the transmittance peaks and the dips as a function of the incident angle for the s-polarization and the p-polarization, respectively. As discussed above, we can see a spatial gap (a disc repancy) between the calculated peak positions and the measured peak positions. For both polarizations, the gap of the maximum transmittance peaks is a bout 200 nm and that of the second highest peaks is about 400 ~ 600 nm. But the positions of the dips between the calculation and the measurement are well matched. For the ppolarization, Figure 6-9 shows the splitting of the peak and the dip when the incident angle increases. Drawbacks of Surface Plasmon and CDEW Another interesting feature that we observe is that there exists a resonant transmission in the case of s-polarization. As shown in Chapter 2, the surface plasmon

PAGE 96

83 does not exist for s-polarized incident light. This means that the surface plamon cannot be the reason for resonant transmission with s-pol arization. Moreno et al. [61] reported in their paper that a resonant transmission is al so possible for s-polarization. They proposed that the resonant transmission is not due to the surface plasmon, but due to a coupling of the incident light to surface mode. As we noticed, there is no difference between spolarization and p-polarization for normal incidence due to the geometrical symmetry. Therefore, we cannot say that the surface pl asmon is only responsible for the resonant transmission of p-polarization case, while something else is responsible for the transmission of s-polarization. Therefore, at least, we can say that the resonant transmission on both sand ppolarizations is not mainly due to the surface plasmon. In addition to this inappropr iateness of the surf ace plasmon for the explanation of the enhanced transmission with s-polarization, in their paper [9], Lezec at al. claimed that the surface plasmon is not responsible for th e enhanced transmission of sub-wavelength hole arrays because of the following reasons : 1) the difference of the peak positions between the surface plasmon model and experi mental data (we already discussed about this previously), 2) an observation of the e nhanced transmission of th e hole arrays in Cr for NIR region and tungsten for VIS region whic h do not support the surface plasmon, 3) the demonstration of the enhanced transmissi on with numerical simulation for hole arrayz in a perfect metal that also do not support the surface plasmon. In contrast, the CDEW cannot explain some parts of experimental features. First, the CDEW model cannot explain the spectra l variations of spolarization and ppolarization as a function of the incident a ngle because the CDEW is based on the scalar diffraction theory [50], so it does not depe nd on polarization directions. Second, J.

PAGE 97

84 Gomez Rivas et al. [24] proposed in their paper about the enhanced transmission in terahertz (THz) region that th e enhanced transmission of su b-wavelength hole array in a doped silicon film depends on temperature, beca use the mobility of the charge carriers in the doped silicon film depends on temperat ure. This means that the enhanced transmission of hole arrays on the doped silicon is attributed to the charge carriers as the electrons in a metal film. Th is could be an evidence of that the surface plasmon is responsible for the enhanced transmission in the metal. Dependence of Hole Shape, Size and Polarization Angle on Transmission In the previous chapter, we showed th e transmittance of the different hole array structures. We have seen that the transmitta nce of each hole array varied with the inplane polarization angle except for the squa re hole array due to its symmetry in x and y directions. Now we compare th ree different hole arrays, squa re hole array, rectangular hole array and slit array, with the same pol arization angle. Figure 6-10 and Figure 6-11 show transmittance of the three hole arrays with pol arization angles of 0 and 90 respectively. As each hole array has an open fraction which is diffe rent from those of other hole arrays, we rescaled the x -axis with transmittance divided by open fraction to compare more directly the data for the diffe rent hole array. The open fractions for the square hole array, rectangul ar hole array and slit arra y are 18 %, 29 % and 50 %, respectively. For the polarization angle of 0 Figure 6-10 (a) shows schematic diagrams comparing three different arrays with the polarization angle of 0 and the lower panel shows the transmittance of those arrays with the same polarization angle. The transmittance of the square hole array (A18-1) shows the maximum peak intensity of 3.3

PAGE 98

85 at 2940 nm. But, the intensity of the maxi mum peak of the rectangular hole array decreases to 1.5. Finally, this maximum peak disappears for the slit array. The position of the maximum peak shifts to shorter wavelengt hs slightly with increasing length of hole edge parallel to polarization di rection. Thus, the intensity of maximum peak is strongly dependent on the length of hole edge parall el to polarization direction, whereas the position of the maximum peak is not affected by changing the length of hole edge parallel to polarization direction. For the peak pos itions, there is not e nough space in shorter wavelengths for the peak to be shifted because the shift to shorter wavelengths is stopped by the dip at 2800 nm. In addition, we can see a change in the dips at 2800 nm and 2000 nm. The dips in the transmittance of the square hole array are we ll established. But, those dips rise up in the transmittance of the rectangular hole array. These dips finally disappear for the slit array. As we mentioned in the previous chap ter, we understand this disappearance of the dips for the slit array because ther e is no grating structure in the 0 polarization angle in the slit array. But, for the rectangular hole array, even though the rectangular hole array has a grating structure with a period of 2 m, which is the same as the period of square hole array, in the 0 polarization angle, the transmittance minimum is less well defined. The increase in the transmittance at the mini ma is not due to the increase of the open fraction because we already rescaled the y-axis with transmittance divided by open fraction. Thus, the effect of larger open frac tion is eliminated. The only parameter that we consider here is the length of hole edge parallel to the polarization angle of 0 which is different in each array. This indicates that the spectral feature of dips in transmittance measured with a certain polari zation direction is not only de pendent on the period of hole

PAGE 99

86 array in the direction parallel to polarization, but also on the length of hole edge parallel to the polarization direction. Another interesting feature in these transmittance is th e intensity of the second highest peak. Different from the maximum peak spectra, the second highest peak in each spectrum shows the intensity which is the sa me as the open fraction of each array. Figure 6-11 shows schematic diagrams comp aring the three different arrays with the polarization angle of 90 and the lower panel shows the transmittance of the three hole arrays with the same polar ization angle. Same as the 0 polarization angle, the transmittance of the square hole array with the polarization angle of 90 shows the maximum peak at 2940 nm. In the transmittan ce of the rectangular hole array, the maximum peak shifts to longe r wavelengths and shows a lowe r intensity with a broader line-width. The transmission spectrum of slit array shows that the peak shifts even more to longer wavelengths and has the lowest intensity with th e broadest line-width. The y axis of these spectra is also rescaled with transmittance divided by open fraction, so the effect of open fraction in the transmittance is eliminated. As we mentioned before, we observed th e red shift of the maximum peak with increasing the dimension of hole edge which is perpendicular to po larization direction. The maximum peaks of the rectangular hole ar ray and the slit array occur at 3300 nm and 4000 nm, which are shifted 350 nm and 1050 nm from the maximum peak position of the square hole array, respectively. This means that the position of the maximum peak is strongly dependent on the length of hole edge pe rpendicular to the polarization direction. In addition to the red shift of the maximum peak, the transmittance show a lesser maximum peak intensity and a broader line-wid th with increasing the length of hole edge

PAGE 100

87 perpendicular to the polarization direction. This observation tells us two different cases: first, the resonant transmission becomes str onger with a shorter ho le edge, which shows the strong and sharp peak, second, the direct transmission from the front surface to the back through the bigger holes becomes strong er with longer hole edge, which shows the low and broad transmittance peak. The second highest peak is also ve ry interesting in the case of 90 polarization angle. The second highest peak shows almost the same features (the peak position, the intensity and the line-width) with increasing the length of hole edge perpendicular to the polarization direction. This is very different from the spect ral behavior of the maximum peak. But, we are still not sure what gives this difference between the maximum peak and the second highest peak. The dips appear with a similar intensity at the fixed positions which are 2800 nm and 2000 nm in all three transmission spectra ex cept the dips of the sl it array are a little higher than others. This is absolutely due to the same periodic grating structures of the three hole arrays in the polarization direction of 90 CDEW and Trapped Modes for Transmi ssion Dependence on Hole Size The CDEW model predicts the red-shift a nd the broader line-width for larger holes. It explains those features with a reduction of the effective number of hole that contributes to the resonant transmission. When the hole size becomes bigger, the bigger holes act as leakage channels for the CDEW, so each hol e is reached by CDEWs from fewer holes. This effective reduction in the number of holes contributing to the resonant transmission causes a weakness of resonant transmission, thus the transmittance shows the red-shift and the broadening of the peak.

PAGE 101

88 The trapped electromagnetic mode also expl ains the larger hole effect. The trapped mode is a long-lived quasi -stationary state that exists in th e vicinity of structures and is responsible for the resonant transmission. If the hole becomes bigger, the trapped mode becomes short-lived rather than long-lived, then the diffractive scattering dominates in transmission process. Thus, for the larger holes, the transmittance spectra lose their resonant features such as a strong and na rrow peak, but show the red-shift and the broadening of the peak instead.

PAGE 102

89 (a) (b) Figure 6-10. Transmittance of square, rectangular and slit arrays with polarization angle of 0 (a) Schematic diagrams and (b) transmittance of the arrays. The transmittance is normalized with open fraction of each hole array. Square Rectangle E E d 1.5d E Slit

PAGE 103

90 (a) (b) Figure 6-11. Transmittance of square, rectangular and slit arrays with polarization angle of 90 (a) Schematic diagrams and (b) transmittance of the arrays. The transmittance is normalized with open fraction of each hole array. Square Rectangle EE Slit E

PAGE 104

91 CHAPTER 7 CONCLUSION In this dissertation, we measured tr ansmission spectra of sub-wavelength hole arrays as functions of the geometrical parame ters of the hole arrays the incident angle and polarization, for two values of the refrac tive indices of dielectric materials. The subwavelength hole arrays that were measured in cluded square hole arrays with different hole sizes and periods, a recta ngular hole array, a slit array and a square hole array on a rectangular grid. Theoretical models explaining the enhan ced transmission of sub-wavelength hole array; the surface plasmon, CDEW and Fano pr ofile analysis, were discussed and their predictions were compared with the experimental transmittance. What we presented and discussed in this dissertation are as follows: First, we calculated the positions of tr ansmittance peaks and dips with the surface plasmon equation and the diffr action grating equation, and compared these with the experimental data. This comparison showed di screpancies between th e peak positions of the calculation and the measurement. In co ntrast, the positions of dips from the calculation are well matched with the measured data. This discrepanc y in the position of the peaks might be due to the approximati ons of the surface plam on model which are the dispersion relation of plane interface, the long-wavelength approximation and an ignorance of the interaction betw een the front and back surface. Second, we demonstrated transmittance as a function of the angle of incidence. For s-polarized light, the wavelength of the tran smittance maxima and that of the neighboring

PAGE 105

92 dip both shift slightly to shor ter wavelengths, For p-polarizat ion, the same peak and dip split into two peaks (and two dips), and the separated two peaks (and two dips) shift in opposite directions. We explai ned this different spectral behavior between sand ppolarization with the surface plasmon equati on and the diffraction grating equation for oblique incidence as follows. Th e s-polarized light excites (0, j ) and (0, – j ) modes along y -axis which are governed by the j2 term in the equations, so that these two mode are degenerate, thus, they do not show a separa tion of peak or dip. In contrast, the ppolarized light excites ( i 0) and (– i 0) modes along the x -axis and these modes are affected by – i term in the equations. This result means that the two modes are separated by the – i term. Thus, the ( i 0) mode shifts to shorter wavelengths, while the (– i 0) mode shifts to longer wavelengths. In addition, transmittance measured with spolarized incident light, as well as ppolarized incident light, showed enhanced tr ansmittance peaks. This transmission feature conflicts with the surface plasmon theory because no surface plasmon with s-polarization exists due to the boundary conditions. Ther efore, the surface plasmon may not be a critical effect for the enhanced tran smission of sub-wavelength hole arrays. Third, we tested the dependence of hol e shape and size by changing the in-plane polarization angle. For arrays of rectangular holes and slits, the transmittance maxima showed higher intensities and red-shifts when the polarization direction was perpendicular to the longer edge of the hole. Moreover, the maxima show stronger resonant features when the edge of hole perpendicular to the polarization direction becomes shorter. When the edge becomes longer, the transmission peaks show lower intensities, broader line-widths and red-shifts This suggests that th e larger hole size gives

PAGE 106

93 a lesser contribution of res onant transmission but more contribution of direct transmission. The dips and the other peaks in the transmittance are also important. We found that the positions of dips are gove rned by the diffraction grating equation. For example, the dips are very strongly fixed at their positions, if the period of hole array in the direction of polarization was kept the same, then they do not shift with changes in hole size. The second highest peak showed almost the same spectral features (p eak intensity, peak position and line-width) in most of the tran smittance spectra, which is quite different from the spectral behavior of the maximum p eak. We are still not sure what gives this difference. With this work we think that the main contribution of the enhanced transmission of sub-wavelength hole arrays comes from the interference of electromagnetic waves diffracted by hole array. There are two di ffracted waves, a surface wave (CDEW or trapped mode) and a directly transmitted wave. The surface wave is more dominant when the holes are smaller, giving resonant transmi ssion features. In contrast, when the holes are larger, the directly transmitted wave is dominant, giving less resonant transmission features. However, there still exists surface plasmons in the hole array, even though their effect on the transmission is smaller than that of the diffracted waves. For future work, we need to study more systematically the dependences of hole size and film thickness on the transmittance. This additional work will provide a clearer understanding of the enhanced transmission. Also, the measurement of reflectance will be needed for a complete study of optical pr operties of sub-wavelength hole arrays. Reflectance measurements will probably give an evidence of surface wave mode on the

PAGE 107

94 metal surface by observing absorption features. In addition, numerical simulations will be essential to establish an appropriate theo retical background for this optical phenomenon. We need to measure transmittance at different detection angles which means meaning transmittance at different diffraction orders.

PAGE 108

95 APPENDIX A TRANSMITTANCE DATA OF DO UBLE LAYER SLIT ARRAYS

PAGE 109

96

PAGE 110

97

PAGE 111

98

PAGE 112

99

PAGE 113

100

PAGE 114

101

PAGE 115

102

PAGE 116

103

PAGE 117

104

PAGE 118

105

PAGE 119

106

PAGE 120

107 APPENDIX B POINT SPREAD FUNCTIONS AND FOCUSING IMAGES OF PHOTON SIEVES

PAGE 121

108 Focal length = 50.0 mm Focal length = 50.5mm

PAGE 122

109 Focal length = 51.2mm

PAGE 123

110

PAGE 124

111 500 nm wavelength light 600 nm wavelength light

PAGE 125

112

PAGE 126

113 500 nm wavelength light 600 nm wavelength light

PAGE 127

114

PAGE 128

115 500 nm FZP 600 nm FZP

PAGE 129

116

PAGE 130

117 500 nm wavelength light 600 nm wavelength light

PAGE 131

118

PAGE 132

119 500 nm wavelength light 600 nm wavelength light

PAGE 133

120

PAGE 134

121 500 nm wavelength light 600 nm wavelength light

PAGE 135

122

PAGE 136

123 49.74 mm focal length 50.98 mm focal length

PAGE 137

124 51.45 mm focal length 51.92 mm focal length

PAGE 138

125 52.38 mm focal length 53.91 mm focal length

PAGE 139

126

PAGE 140

127 42.19 mm focal length 43.50 mm focal length

PAGE 141

128 44.75 mm focal length 49.23 mm focal length

PAGE 142

129 51.45 mm focal length

PAGE 143

130

PAGE 144

131 53.38 mm focal length 54.54 mm focal length

PAGE 145

132 58.33 mm focal length 59.18 mm focal length

PAGE 146

133

PAGE 147

134 51.45 mm focal length 52.38 mm focal length

PAGE 148

135

PAGE 149

136 APPENDIX C TRANSMITTANCE DATA OF BULL’S EYE STRUCTURE Optical microscopic image of 2 m period bull’s eye structure

PAGE 150

137

PAGE 151

138

PAGE 152

139

PAGE 153

140

PAGE 154

141

PAGE 155

142 LIST OF REFERENCES 1. W. L. Barnes, A. Dereux and T. W. Ebbesen, Nature 424, 824 (2003) 2. H. A. Bethe, Phys. Rev 66, 163 (1944) 3. S. Wedge, I. R. Hooper, I. Sage and W. L. Barnes, Phys. Rev B 69, 245418 (2004) 4. D. K. Gifford and D. G. Hall, Appl. Phys. Lett 80, 3679 (2002) 5. W. Sritravanich, S. Durant, H. Lee, C. Sun and X. Zhang, J. Vac. Sci. Technol. B 23, 2636 (2005) 6. X. Luo and T. Ishihara, Appl. Phys. Lett 84, 4780 (2004) 7. T. W. Ebbesen, H. J. Lezec, H. F. Ghaemi, T. Thio and P. A. Wolff, Nature 391, 667 (1998) 8. H. Reather, Surface Plasmons on Smooth and Rough Surfaces and on Gratings (Springer-Verlag, Berlin, Germany, 1988) 9. H. J. Lezec and T. Thio, Opt. Exp 12, 3629 (2004) 10. M. M. J. Treacy, Appl. Lett. 75, 606 (1999) 11. M. M. J. Treacy, Phys. Rev. B 66, 195105 (2002) 12. M. Sarrazin, J. Vigneron and J. Vigoureux, Phys. Rev. B 67, 085415 (2003) 13. C. Genet, M. P. van Exter and J. P. Woerdman, Opt. Comm 225, 331 (2003) 14. C. Genet, M. P. van Exter and J. P. Woerdman J. Opt. Soc. Am. A 22, 998 (2005) 15. U. Fano, Phys. Rev. 124, 1866 (1961) 16. H. F. Ghaemi, T. Thio, D. E. Grupp T. W. Ebbesen and H. J. Lezec, Phys. Rev. B 58, 6779 (1998) 17. W. Fan, S. Zhang, B. Minhas, K. J. Malloy and S. R. J. Brueck, Phys. Rev. Lett 94, 033902 (2005) 18. H. Cao and A. Nahata, Opt. Exp 12, 1004 (2004)

PAGE 156

143 19. H. Cao and A. Nahata, Opt. Exp 12, 3664 (2004) 20. X. Shou, A. Agrawal and A. Nahata, Opt. Exp 13, 9834 (2005) 21. A. K. Azad, Y. Zhao and W. Zhang, Appl. Phys. Lett 86, 141102 (2005) 22. D. Qu, D. Grischkowsky and W. Zhang, Opt. Lett 29, 896 (2004) 23. J. Gomez Rivas, C. Schotsch, P. Haring Bolivar and H. Kurz, Phys. Rev. B 68, 201306 (2003) 24. J. Gomez Rivas, P. Haring Bolivar and H. Kurz, Opt. Lett 29, 1680 (2004) 25. A. Degiron, H. J. Lezec, N. Yamamoto and T. W. Ebbesen, Opt. Comm 239, 61 (2004) 26. F. J. Garcia-Vidal, E. Moreno, J. A. Porto and L. Martin-Moreno, Phys Rev. Lett 95, 103901 (2005) 27. T. Thio, K. M. Pellerin, R. A. Li nke, H. J. Lezec and T. W. Ebbesen, Opt. Lett 26, 1972 (2001) 28. H. J. Lezec, A. Degiron, E. Devaux, R. A. Linke, L. Martin-Moreno, F. J. GarciaVidal, T. W. Ebbesen, Science 297, 820 (2002) 29. T. Thio, H. J. Lezec, T. W. Ebbesen, K. M.Pellerin, G. D. Lewen, A. Nahata and R. A. Linke, Nanotechnology 13, 429 (2002) 30. L. Martin-Moreno, F. J. Garcia-Vidal, H. J. Lezec, K. M. Pellerin, T. Thio, J. B. Pendry and T. W. Ebbesen, Phys. Rev. Lett 86, 1114 (2001) 31. L. Salomon, F. Grillot, A. V. Zayats and F. de Fornel, Phys. Rev. Lett 86, 1110 (2001) 32. W. L. Barnes, W. A. Murray, J. Dint inger, E. Devaux and T. W. Ebbesen, Phys. Rev. Lett 92, 107401 (2004) 33. K. G. Lee, Q-Han Park, Phys. Rev. Lett 95, 103902 (2005) 34. A. V. Zayats, I. I. Smolyaninov and A. A. Maradudin, Phys. Rep 408, 131 (2005) 35. F. J. Garcia de Abajo, R. Go mez-Medina and J. J. Saenz, Phys. Rev. E 72, 016608 (2005) 36. F. J. Garcia de Abajo, J. J. Saenz, I. Campillo and J. S. Dolado, Opt. Exp. 14, 7 (2006) 37. F. J. Garcia de Abajo, Opt. Lett 10, 1475 (2002)

PAGE 157

144 38. Che-Wei Chang, A. K. Sarychev and Shalaev, Laser Phys. Lett 2, 351 (2005) 39. A. G. Borisov, F. J. Garcia de Abajo, S. V. Shabanov, Phys. Rev. B 71, 075408 (2005) 40. N. Peyghambarian, S. W. Koch and A. Mysyrowicz, Introduction to semiconductor optics (Prentice-Hall Inc. Eaglewood Cliffs, New Jersey, 1993) 41. F. Wooten, Optical properties of solids (Academic press, New York, New York and London, England, 1972) 42. M. A. Ordal, L. L. Long, R. J. Bell, S. E. Bell, R. R. Bell, R. W. Alexander, Jr. and C. A. Ward, Appl. Opt 22, 1099 (1983) 43. R. Gordon, A. G. Brolo, A. McKinnon, A. Rajora, B. L eathem and K. L. Kavanagh, Phys. Rev. Lett 92, 037401 (2004) 44. K. J. Klein Koerkamp, S. Enoch, F. B. Se gerink, N. E. van Hulst and L. Kuipers, Phys. Rev. Lett 92, 183901 (2004) 45. K. L. vander Molen, K, J. Klein Koerkamp S. Enoch, F. B. Segerink, N. F. van Hulst and L. Kuipers, Phys. Rev. B 72, 045421 (2005) 46. A. Degiron and T. W. Ebbesen, J. Opt. A: Pure Appl. Opt 7, S90 (2005) 47. G. Gay, B Viaris de Lesegno, R Mathevet, H. J. Lezec and J. Weiner, J. Phys.: Conference series 19, 102 (2005) 48. G. Gay, O. Alloschery, B. Viaris de Lesegno, C. O’Dwyer and J. Weiner, Nature Phys 2, 262 (2006) 49. G. Gay, O. Alloschery, B. Vi aris de Lesegno and J. Weiner, Arxiv: physics /0602119 v1 (2006) 50. M. W. Kowarz, Appl. Opt 34, 3055 (1995) 51. Jungseek Hwang, Ph.D. dissertation Department of Physics, University of Florida, Gainesville (2001) 52. E. Hecht, Optics 2nd edition. (Addison-Wesley P ublishing Company, Reading, Massachusetts, 1987) 53. Oriel Instruments, Transmittance of optical materials May 2006, http://www.lotoriel.com/site/site_down/ls _opticalmaterials_deen.pdf 54. T. Vallius, J. Turunen, M. Mansuripur and S. Honkanen, J. Opt. Soc. Am. A 21, 456 (2004)

PAGE 158

145 55. A. Degiron, H. J. Lezec, W. L. Barnes and T. W. Ebbesen, Appl. Phys. Lett 81,4327 (2002) 56. E. Altewischer, M. P. van Exter and J. P. Woerdman, Nature 418, 304 (2002) 57. E. Moreno, F. J. Garcia-Vidal, D. Erni, J. Ignacio Cirac and L. Martin-Moreno, Phys. Rev. Lett 92, 236801 (2004) 58. A. Krishnan, T. Thio, T. J. Kim, H. J. Lezec, T. W. Ebbesen, P. A. Wolff, J. Pendry, L. Martin-Moreno, F. J. Garcia-Vidal, Opt. Comm 200, 1 (2001) 59. Technical data sheet of Microposit S1800 series photo resists (Shipley, Marlborough, Massachusetts, May 2006) 60. Technical data sheet of Nano PMMA and Copolymer (MicroChem, Newton, Massachusetts, May 2006) 61. E. Moreno, L. Martin-More no and F. J. Garcia-Vidal, J. Opt. A : Pure Appl. Opt 8, s94 (2006)

PAGE 159

146 BIOGRAPHICAL SKETCH I was born in Seoul, Korea, and grew up with a dream of becoming a famous scientist. It was the time of my gradua tion from Myongji High School when I started thinking about studying physics. In 1987, I entered Chungang University in Seoul and majored in physics. I finished my bachelor’s and master’s degrees in the same university. In 1996, I graduated with my master’s degree and I entered Orion El ectric Company as a research engineer to work on flat panel display devices. I worked in Orion Electric Company for five years, and th en I joined in a research group of ETRI which is one of the national labs in Korea. But, I still want ed to study physics more, and decided to go to the University of Florida. I spent my last five years here in Ga inesville to study physics and now I am finishing my Ph.D.


Permanent Link: http://ufdc.ufl.edu/UFE0015340/00001

Material Information

Title: Transmission properties of sub-wavelength hole arrays in metal films
Physical Description: Mixed Material
Language: English
Creator: Woo, Kwangje ( Dissertant )
Tanner, David B. ( Thesis advisor )
Hebard, Arthur ( Reviewer )
Hill, Stephen O. ( Reviewer )
Hershfield, Selman P. ( Reviewer )
Holloway, Paul H. ( Reviewer )
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2006
Copyright Date: 2006

Subjects

Subjects / Keywords: Physics thesis, Ph.D
Dissertations, Academic -- UF -- Physics

Notes

Abstract: We have measured the optical transmittance of sub-wavelength hole arrays in metal films. We investigated the spectral behavior of transmittance (the peak positions, intensities, line-widths, and the dip positions) as a function of the geometrical parameters of the hole arrays, the angle of incidence, the polarization angle and the refractive indices of the substrates. We calculated the positions of transmittance peaks and dips with equations from the surface plasmon theory and the diffraction theory, and compared the calculated positions of peaks and dips with measured transmittance data. We found that there is a discrepancy of 3 ~ 5% between the peak positions calculated with the surface plasmon equation and the peak positions in the measured transmittance data. We explain this discrepancy as possibly due to the approximations of the surface plasmon equation. However, the positions of the dips in the spectra, as calculated with the diffraction grating equation, were well matched to the measured data. We also observed splittings and shifts of the peaks and dips when changing the angle of incidence and the polarization of the light. We confirmed this spectral behavior qualitatively with calculation of momentum conservation equations for oblique incidence and showed that the diffraction modes are degenerate for s-polarization, while the modes are not degenerate for p-polarization. We studied the dependence of hole size and shape on the transmittance while also changing the in-plane polarization angle. We observed that the transmittance peak is strongly dependent on the length of the hole edge perpendicular to the polarization direction. In addition, we investigated the dependence on film thickness and the refractive index of dielectric substrate.
Abstract: array, diffraction, hole, plasmon, subwavelength, surface, transmission
General Note: Title from title page of source document.
General Note: Document formatted into pages; contains 159 pages.
General Note: Includes vita.
Thesis: Thesis (Ph.D.)--University of Florida, 2006.
Bibliography: Includes bibliographical references.
General Note: Text (Electronic thesis) in PDF format.

Record Information

Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
System ID: UFE0015340:00001

Permanent Link: http://ufdc.ufl.edu/UFE0015340/00001

Material Information

Title: Transmission properties of sub-wavelength hole arrays in metal films
Physical Description: Mixed Material
Language: English
Creator: Woo, Kwangje ( Dissertant )
Tanner, David B. ( Thesis advisor )
Hebard, Arthur ( Reviewer )
Hill, Stephen O. ( Reviewer )
Hershfield, Selman P. ( Reviewer )
Holloway, Paul H. ( Reviewer )
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2006
Copyright Date: 2006

Subjects

Subjects / Keywords: Physics thesis, Ph.D
Dissertations, Academic -- UF -- Physics

Notes

Abstract: We have measured the optical transmittance of sub-wavelength hole arrays in metal films. We investigated the spectral behavior of transmittance (the peak positions, intensities, line-widths, and the dip positions) as a function of the geometrical parameters of the hole arrays, the angle of incidence, the polarization angle and the refractive indices of the substrates. We calculated the positions of transmittance peaks and dips with equations from the surface plasmon theory and the diffraction theory, and compared the calculated positions of peaks and dips with measured transmittance data. We found that there is a discrepancy of 3 ~ 5% between the peak positions calculated with the surface plasmon equation and the peak positions in the measured transmittance data. We explain this discrepancy as possibly due to the approximations of the surface plasmon equation. However, the positions of the dips in the spectra, as calculated with the diffraction grating equation, were well matched to the measured data. We also observed splittings and shifts of the peaks and dips when changing the angle of incidence and the polarization of the light. We confirmed this spectral behavior qualitatively with calculation of momentum conservation equations for oblique incidence and showed that the diffraction modes are degenerate for s-polarization, while the modes are not degenerate for p-polarization. We studied the dependence of hole size and shape on the transmittance while also changing the in-plane polarization angle. We observed that the transmittance peak is strongly dependent on the length of the hole edge perpendicular to the polarization direction. In addition, we investigated the dependence on film thickness and the refractive index of dielectric substrate.
Abstract: array, diffraction, hole, plasmon, subwavelength, surface, transmission
General Note: Title from title page of source document.
General Note: Document formatted into pages; contains 159 pages.
General Note: Includes vita.
Thesis: Thesis (Ph.D.)--University of Florida, 2006.
Bibliography: Includes bibliographical references.
General Note: Text (Electronic thesis) in PDF format.

Record Information

Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
System ID: UFE0015340:00001


This item has the following downloads:


Full Text












TRANSMISSION PROPERTIES OF SUB-WAVELENGTH HOLE ARRAYS IN
METAL FILMS

















By

KWANGJE WOO


A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY

UNIVERSITY OF FLORIDA


2006

































Copyright 2006

by

Kwangj e Woo















ACKNOWLEDGMENTS

For last 5 years for my Ph.D. work, there are many people whom I have to thank

for their support, advice and encouragement.

First, I would like to thank my advisor, Professor David B. Tanner. Since I have

become his research assistant, I have received so much valuable advice, encouragement

and support.

Also, I would like to thank Professor Arthur F. Hebard, Professor Stephen O. Hill,

Professor Selman P. Hershfield and Professor Paul H. Holloway for serving on my

supervisory committee.

It was a great time for me to work in Prof Tanner's lab for last four years because I

had good colleagues in this lab: Dr. Andrew Wint, Dr. Hedenori Tashiro, Dr. Maria

Nikolou, Dr. Minghan Chen, Haidong Zhang, Naveen Margankunte, Nathan Heston,

Daniel Arenas and Layla Booshehri. I would like to thank these people.

Especially, I would like to thank my collaborator Sinan Selcuk for supplying

samples, scientific discussions and a truthful friendship.

I would like to thank my parents. They have supported me throughout my life.

Finally, my wife and children, Ohsoon, Jisoo and Jiwon, have supported me with their

love and patience. I would like to express my deepest thanks to them.
















TABLE OF CONTENTS

page

A C K N O W L E D G M E N T S ................................................................................................. iii

LIST OF TABLES ....................................................... ............ .............. .. vii

L IST O F FIG U R E S .............. ............................ ............. ........... ... ........ viii

ABSTRACT ........ .............. ............. .. ...... .......... .......... xii

CHAPTER

1 IN TR OD U CTION ............................................... .. ......................... ..

Background and M otivation ...................................................... .......................
O rg animation .................................................. .......................... 2

2 RIVIEW OF SURFACE PLASMON AND DIFFRACTION THEORY ..................4

Bethe's Theory for Transmittance of a Single Sub-Wavelength Hole.........................5
Surface P lasm on ................................................... ...................... 7
D definition of Surface Plasm on ........................................ ......................... 7
Dispersion Relation of Surface Plasmon............... ..............................................7
Dispersion relation for the p-polarization ............................................... 8
Dispersion relation for the s-polarization...............................................10
D ispersion curves ......... .... ........ ........................ .. ....... .................12
Propagation Length of the Surface Plasmon ...................................................14
Surface Plasmon Excitation................. ...... ........ .................14
Mechanism of Transmission via Surface Plasmon Coupling in Periodic Hole
A rra y ....................................... ............................................ ............... 1 7
CDEW (Composite Diffractive Evanescent Wave) .................. ............... 19
Basic Picture of the CDEW ................ ..... ....................... .........19
CDEW for an Aperture with Periodic Corrugation ................ ...............22
CDEW for a Periodic Sub-Wavelength Hole Array............... ............... 23
F ano P profile A naly sis .............................. .... ...................... .. ...... .... ...... ...... 25

3 IN STR U M E N TA TIO N ................................................................... .....................29

Perkin-Elmer 16U Monochromatic Spectrometer.................................................29
Light Sources and D etectors.......................................... ........... ............... 29









Grating Monochromator ........... ..... .............. ............... 30
M onochrom ator configuration .......................................... ............... 31
Resolution of monochromator............ ......... .............................32
The D iffraction G rating .............................................. ..... ....................... 33
Grating equation and diffraction orders ....................................... .......... 33
Blaze angle of the grating................................ ........................ ......... 34
R solving pow er of grating ...................... ......... ...................................... 34
Bruker 113v Fourier Transform Infrared (FTIR) Spectrometer..............................35
Interferom eter ............... .. ......................................... .. .. ......... 35
Description of FTIR Spectrometer System ............... ............................... 38

4 SAM PLE AND M EASUREM ENT ........................................ ........ ............... 41

Sample Preparation..................... .......................... .......... 41
S u b stra te s .............................................................................................................. 4 1
M easurem ent Setup ............................................................... .... .. ....43

5 EXPERIMENTAL RESULTS ............................................................................46

Enhanced Optical Transmission of Sub-wavelength Periodic Hole Array ...............46
Comparison of Enhanced Transmission with Classical Electromagnetic Theory......47
Dependence of Period, Film Thickness and Substrate on Transmission....................48
Dependence on Period of Hole Array .................................................. ... ........... 49
Dependence on the Thickness of Metal Film.............. .... .................50
Dependence on the Substrate M material ..................................... ............... 52
Dependence on the Angle of Incidence.............................. ...............54
Dependence on Hole Shape ......... ..... ......... .......................... 58
Squ are H ole A rray s ........................... ......................... .. ...... .. ...... ............58
Rectangular Hole Array ......... .. .. ......... ............... ............... 59
Slit A rray s ............... ................. ... ............. .............................. 6 1
Transmission of Square Hole Array on Rectangular Grid ................................ 62
Refractive Index Symmetry of Dielectric Materials Interfaced with Hole Array ......63

6 ANALYSIS AND DISCU SSION ........................................ ......................... 68

Prediction of Positions of Transmission Peaks......... ................ .... ..................... 68
Comparison of Calculated and Measured Positions of Transmittance Peaks and
D ip s .......................... ....... ...... .................................... ............... 7 0
Dependence of the Angle of Incidence on Transmission.................................74
Drawbacks of Surface Plasmon and CDEW ................................... ............... 82
Dependence of Hole Shape, Size and Polarization Angle on Transmission ..............84
CDEW and Trapped Modes for Transmission Dependence on Hole Size.................87

7 C O N C L U SIO N ......... ......................................................................... ........ .. ..... .. 9 1

APPENDIX

A TRANSMITTANCE DATA OF DOUBLE LAYER SLIT ARRAYS ....................95









B POINT SPREAD FUNCTIONS AND FOCUSING IMAGES OF PHOTON
S IE V E S ...................................... .................................................. 10 7

C TRANSMITTANCE DATA OF BULL'S EYE STRUCTURE............................136

L IST O F R E F E R E N C E S ...................... .. .. ......... .. .................................................. 142

BIOGRAPHICAL SKETCH ................ ............................................ ............... 146
















LIST OF TABLES


Table page

4-1 List of the periodic sub-wavelength hole arrays .................................................43

6-1 Calculated positions of surface plasmon resonant transmittance peaks for three
interfaces of 2000 nm period hole arrays at normal incidence (Ed of air, fused
silica and ZnSe are 1.0, 2.0 and 6.0, respectively)................................ ...........69

6-2 Calculated positions of transmittance dips for three interfaces of 2 atm period
hole arrays at normal incidence (Ed of air, fused silica and ZnSe are 1.0, 2.0 and
6.0, respectively) ......................................................................72















LIST OF FIGURES


Figure p

2-1 Schematic diagram for p-polarized (TM) light incident on a dielectric/metal
interface ............................................................... .... ..... ......... 12

2-2 Schematic diagram for s-polarized (TE) light incident on a dielectric/metal
interface ............................................................... .... ..... ......... 12

2-3 Dispersion curves of surface plasmon at air/metal interface and at quartz/metal
interface, light lines in air and fused silica.................................. ............... 13

2-4 Schematic diagrams of (a) the excitation of the surface plasmon by the incident
photon on a metallic grating surface and (b) the dispersion curves of the incident
photon, the scattered photon and the surface plasmon...........................................15

2-5 Schematic diagrams of the excitation of the surface plasmon by the incident
photon on a two dimensional metallic grating surface ...........................................18

2-6 Schematic diagram of transmission mechanism in a sub-wavelength hole array.... 18

2-7 Geometry of optical scattering by a hole in a real screen in (a) real space and (b)
k-space for a range that kx is close to zero.................................... ............... 21

2-8 CDEW lateral field profile at z = 0 boundary, a plot of Eq. (2-44) ..... ......... 22

2-9 CDEW picture for an aperture with periodic corrugations on the input and
output surfaces. Red arrows indicate the CDEWs generated on the input and
ou tpu t su races ................................................. ................ 2 4

2-10 A CDEW picture for a periodic sub-wavelength hole array. Red arrows indicate
the CDEWs generated on the input and output surfaces .......................................24

2-11 Schematic diagrams for Fano profile analysis. .............................. ......... ...... .27

2-12 A schematic diagram of the non-resonant transmission (Bethe's contribution)
and the resonant transmission (surface plasmon contribution) .............................27

2-13 Schematic diagram of the interference between the resonant and non-resonant
diffraction in transmission of sub-wavelength hole array ................... ..............28

3-1 Schematic diagram ofPerkin-Elmer 16U monochromatic spectrometer.................30









3-2 Schematic diagram of the Littrow configuration in the monochromator of
Perkin-Elmer 16U spectrometer...................... ..... ............................ 31

3-3 Schematic diagram of a reflection grating. ................................... ............... 33

3-4 Schematic diagram of a blazed grating ........................................ ............... 34

3-5 Schematic diagram of Michelson interferometer................. ............... .............36

3-6 Schematic diagram of the Bruker 113v FTIR spectrometer.................................39

4-1 SEM images of periodic hole arrays samples ..............................42

4-2 Picture of the sample holder used to measure transmittance with changing the
angle of incidence and the in-plane azimuthal angle ............................................44

5-1 Transmittance of the square hole array (A14-1) and a silver film ...........................47

5-2 Comparison between Bethe's calculation and the transmittance measured with
the square hole array (A 14-1)........................................................ ............... 48

5-3 Transmittance of square hole arrays with periods of 1 tm (A15) and 2 tm (A18-
1).............. .................... ...................................... ........ ...... 4 9

5-4 Transmittance vs. scaling variable, ks = k/(nd x period), for the square hole
arrays of 1 tm period (A15) and 2 tm period (A18-1) made on fused silica
su b states (n d = 1.4 ) ............... ............................................. ................ 5 1

5-5 (a) Transmittance vs. wavelength (b) transmittance vs. scaling variable, ks =
X/(nd x period), for the square hole arrays of 2 tm period (A14-1) made on a
fused silica substrate (nd = 1.4) and a ZnSe substrate (nd = 2.4)...........................53

5-6 Transmittance of a square hole array (A14-1) with three different polarizations
at norm al incidence ............................................ ................. ........ 54

5-7 Measurement of transmittance with s-polarized incident light as a function of the
incident angle. ........................................................................56

5-8 Measurement of transmittance with p-polarized incident light as a function of
the incident angle. .....................................................................57

5-9 Transmittance of square hole array (A18-1) as a function of polarization angle.
The inset shows a SEM image of the square hole array.................................59

5-10 Transmittance of a rectangular hole array (A18-2) for in-plane polarization
angles of 0 0 and 90 The inset shows a SEM image of the rectangular hole
array ............... .... ... ......... .. ............................................60









5-11 Transmittance of a slit array (A18-3) for in-plane polarization angles of 0 and
90 The inset shows a SEM image of the slit array. ............. ...............61

5-12 Transmittance of a square hole array on a rectangular grid (A18-4) for
polarization angles of 0 45 o and 90 The inset shows a SEM image of the
square hole array in a rectangular grid. .......................................... ............... 62

5-13 Schematic diagram of sample preparation .................................... ............... 65

5-14 Transmittance of a square hole array (A14-1) on fused silica substrate with and
without PR coated on the top ............................................................................65

5-15 Transmittance of a square hole array (A14-1) on ZnSe substrate with and
without PR coated on the top of hole array ....... ........ ......................... ........ 66

5-16 Transmittance of a square hole array (A14-1) on fused silica substrate with and
without PMMA coated on the top of hole array with the second fused silica
substrate attached on the top of PM M A....................................................... 66

6-1 Comparison of calculated peak positions with measured transmittance data.
Transmittance measured with a square hole array (A18-1) is shown. P1, P2 and
P3 are the calculated positions of three transmittance peaks ................................70

6-2 Comparison of the calculated transmittance peaks and dips with the
transmittance measured with a square hole array (A18-1) made on a fused silica
substrate. P1, P2 and P3 are the calculated positions of the first three peaks and
D1, D2 and D3 are the calculated positions of the first three dips...........................73

6-3 Comparison of the calculated transmittance peaks and dips with the
transmittance measured with a square hole array (A14-1) made on a ZnSe
substrate. P4 and P5 are the calculated peak positions and D4 and D5 are the
calculated dip positions for the ZnSe-metal interface. P2, P3, D2 and D3 are the
positions of the peaks and the dips for the air-metal interface.............................74

6-4 Transmittance of a square hole array (A14-1) measured using unpolarized light
at norm al incidence. ........................................... .. .... ......... .. ..... .. 75

6-5 Schematic diagram of an excitation of surface plasmon by the incident light on
two dimensional metallic grating surface.............. ............................. ..............76

6-6 Transmittance with s-polarized incident light...................... ........ ........................ 77

6-7 Transmittance with s-polarized incident light...................... ........ ........................ 78

6-8 Peak and dip position vs. incident angle for s-polarization..................................79

6-9 Peak and dip position vs. incident angle for p-polarization. .............. ...............80









6-10 Transmittance of square, rectangular and slit arrays with polarization angle of
00.. ....................................................89

6-11 Transmittance of square, rectangular and slit arrays with polarization angle of
900. ...................................... .................. .. 90















Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Doctor of Philosophy

TRANSMISSION PROPERTIES OF SUB-WAVELENGTH HOLE ARRAYS IN
METAL FILMS

By

Kwangj e Woo

August 2006

Chair: David B. Tanner
Major Department: Physics

We have measured the optical transmittance of sub-wavelength hole arrays in metal

films. We investigated the spectral behavior of transmittance (the peak positions,

intensities, line-widths, and the dip positions) as a function of the geometrical parameters

of the hole arrays, the angle of incidence, the polarization angle and the refractive indices

of the substrates. We calculated the positions of transmittance peaks and dips with

equations from the surface plasmon theory and the diffraction theory, and compared the

calculated positions of peaks and dips with measured transmittance data. We found that

there is a discrepancy of 3 5% between the peak positions calculated with the surface

plasmon equation and the peak positions in the measured transmittance data. We explain

this discrepancy as possibly due to the approximations of the surface plasmon equation.

However, the positions of the dips in the spectra, as calculated with the diffraction grating

equation, were well matched to the measured data. We also observed splitting and shifts

of the peaks and dips when changing the angle of incidence and the polarization of the









light. We confirmed this spectral behavior qualitatively with calculation of momentum

conservation equations for oblique incidence and showed that the diffraction modes are

degenerate for s-polarization, while the modes are not degenerate for p-polarization. We

studied the dependence of hole size and shape on the transmittance while also changing

the in-plane polarization angle. We observed that the transmittance peak is strongly

dependent on the length of the hole edge perpendicular to the polarization direction. In

addition, we investigated the dependence on film thickness and the refractive index of

dielectric substrate.














CHAPTER 1
INTRODUCTION

Background and Motivation

Recently, many workers in the area of optics have reported very interesting results

in a new regime of optics called nano optics, sub-wavelength optics, or plasmonic optics

[1]. In this area of optics, the physical dimension of objects for optical measurements is

on a sub-wavelength scale. Interestingly, the optical properties of sub-wavelength

structures are different from what we predict from classical electromagnetic theory [2]. In

addition, this new field of optics makes it possible to manipulate light via sub-wavelength

structures. This capability of controlling light attracts a lot of applications in various

fields of science and technology, for instance, Raman spectroscopy, photonic circuits, the

display devices, nanolithography and biosensors [3-6].

Since the first research on enhanced optical transmission of an array of sub-

wavelength holes was reported in 1998 by Ebbesen et al. [7], no theory has explained this

phenomenon, even though a lot of work has been carried out. But theoretical studies are

still actively going on, with the most prominent one being the surface plasmon polariton

(SPP) theory [8]. In addition to the surface plasmon polariton, the diffraction theory is

also a very strong candidate as an explanation of the enhanced transmission of sub-

wavelength hole array [9-11]. Another model [12-14] proposed to explain this enhanced

transmission phenomenon is the superposition of a resonant process and a non resonant

process which shows the Fano profile [15]. Since the surface plasmon polariton model

has some drawbacks [9] and shows a discrepancy between calculated and measured data









[16], other models are considered as strong explanations of this enhanced transmission

phenomenon.

Many experiments also have been done for a wide spectral range. The enhanced

transmission of periodic hole arrays for the optical region, the near-infrared region [17],

and the terahertz (THz) region [18-24] was reported.

Other scientific and technological interest is focused on the enhanced transmission

of a single sub-wavelength aperture. The enhanced transmission of a single plain

rectangular aperture, which depends on the polarization direction, was reported [25, 26].

And an aperture with corrugations on the input side showed an enhanced transmission as

well as a beaming of the transmitted light with corrugations on the output side [27-29].

In this dissertation, we present experimental transmission data for sub-wavelength

hole arrays as a function of their geometrical parameters, the angle of incidence, the

polarization of the light, and for two values of the refractive index of the dielectric

substrate material. For the theoretical models, we will discuss surface plasmon,

composite diffractive evanescent wave, Fano profile analysis and trapped mode.

Organization

This dissertation consists of seven chapters, including this introduction chapter.

The details of each chapter are as follows:

In Chapter 2, we review the basic theories of surface plasmon and diffraction. The

surface plasmon theory includes surface plasmon excitation by incident light, the

plasmon dispersion relation, and an introduction of the transmission mechanism via

surface plasmon coupling. The diffraction theory includes the CDEW (composite

diffractive evanescent wave) model and Fano profile analysis. In Chapter 3, we describe

our experimental setup for transmission measurement. Two spectrometers (a grating









monochromatic spectrometer and a FTIR spectrometer) are introduced. In Chapter 4, the

sample preparation and the measurement technique with the specifications of samples are

presented.

In Chapter 5, the measured transmittance data are presented. The transmittance data

are shown as a function of the geometrical parameters of hole array, the polarization and

the incident angle of light, and the refractive indices of the substrate material.

In Chapter 6, we analyze and discuss the experimental results based on the surface

plasmon and diffraction theories. We discuss the positions of peaks and dips, spectral

changes with variation of the incident angle and polarization, and the dependence on hole

shape and size. Finally, Chapter 7 has the conclusions of this dissertation and briefly

introduces some additional studies which are necessary for a future study.














CHAPTER 2
REVIEW OF SURFACE PLASMON AND DIFFRACTION THEORY

There are two independent theories which explain the transmission enhancement by

periodic arrays of sub-wavelength holes: the surface plasmon polariton and the

diffraction theory. When the enhanced transmission was reported by Ebbesen and his co-

workers, they interpreted their results with the surface plasmon [7]. The surface plasmon

is still the most generally accepted explanation of the enhanced phenomenon [30-33].

With dispersion relation of the surface plasmon and momentum conservation equation of

periodic grating, one can predict the positions of the enhanced transmission peak pretty

accurately. But the prediction still shows some differences with the experimental results

[16]. For this difference, there might be two reasons. First, the surface plasmon theory is

based on the long-wavelength approximation (A >> d), which means that it does not

depend on the hole size of the structures. Second, the surface plasmon theory, which is

currently used in most papers, is still limited to the dispersion relation for a single

interface between a dielectric and a metal (in which both are infinitely thick) while the

experiments deal with structures containing double interfaces with a finite thickness for

the metal film [34]

As we know, the classical diffraction theory for an electromagnetic wave impinging

on a sub-wavelength aperture in an optically opaque conducting plane predicts an

extremely low transmittance [2]. In this paper, Bethe showed the transmittance intensity

of a sub-wavelength aperture proportional to (d/k)4. But many calculations for diffraction









by periodic hole arrays show an enhanced transmission which is very similar to

experimental data [35-38].

The composite diffractive evanescent wave (CDEW) [9] is one of the diffraction

models explaining the enhanced transmission by periodic structures. The CDEW means a

constructive interference of electromagnetic waves diffracted by periodic sub-wavelength

structure and it is another strong candidate responsible for the enhanced transmission

phenomenon. This diffraction model (CDEW) can explain the enhanced transmission of

hole array in a perfect conductor or in non-metallic materials which the surface plasmon

model cannot explain.

Another transmission model explaining the enhanced transmission is a unifying one

of both the surface plasmon and the diffraction model [12, 13]. This unifying model

proposes an analysis with Fano profile in transmission spectra which is attributed to a

superposition of the resonant process and non-resonant process.

Recently, A. G. Borisov et al. [39] proposed another diffraction model for the

enhanced transmission of sub-wavelength structures. They suggested that the enhanced

transmission of sub-wavelength hole arrays is due to the interference of diffractive and

resonant scattering. The contribution of the resonant scattering comes from the

electromagnetic modes trapped in the vicinity of structures. This trapped electromagnetic

mode is a long-lived quasistationary mode and gives an explanation of extraordinary

resonant transmission.

Bethe's Theory for Transmittance of a Single Sub-Wavelength Hole

Bethe [2] reported that the transmittance of electromagnetic waves through a single

hole in an infinite plane conducting screen, which is very thin but optically opaque, is

very small when wavelength of the incident light is much larger than the hole size. With









this long-wavelength condition, d/k << 1, where d is the diameter of hole and X is

wavelength of the incident light, Bethe has calculated "diffraction cross section" of the

hole for the s- and p-polarization:


A, k4 Cos0 (2-1)
S27r 2

64 d4 1 2 + I
A = 27k4 \ l+Sin 20 (2-2)
P 27r 7 2) 4

The s-polarized (TE mode) wave has an electric field perpendicular to the plane of

incidence whereas the p-polarized (TM mode) wave has a magnetic field perpendicular to

the plane of incidence. These polarizations are schematically shown in Figures 2-1 and 2-

2.

In Eqs. (2-1) and (2-2), one can recognize that the diffraction cross sections for two

polarizations are the same for normal incidence, 0= 0. If the diffraction cross section is

normalized to hole area, the normalized diffraction cross section becomes

A 64 (kd-4 (d 4
=~ 2 23 = T (2-3)
(d 2 27r2 2"A
2\-

2j
where k = k and 2 are wave number and wavelength of the incident wave,

respectively, and d is diameter of hole. This normalized diffraction cross section can be

considered as transmission normalized to hole area, T.

Eq. (2-3) is actually an expression for a circular aperture. If we change the circular

aperture to a rectangular aperture which has a dimension ofD x D, Eq. (2-3) can be

changed as









A 64 (kD)4 D) T (2-4)
2 18 = T (2-4)
D 2 27fr 26 l

Surface Plasmon

The presence of a surface or an interface between materials with different dielectric

constants leads to specific surface-related excitations. One example of this phenomenon

is the surface plasmon. The interface between a medium with a positive dielectric

constant and a medium with negative dielectric constant, such as a metal, can give rise to

special propagating electromagnetic waves called surface plasmons, which stays confined

near the interface.

Definition of Surface Plasmon

Sometimes the surface plasmon is also called the surface plasmon polariton. To

understand this surface plasmon polariton, we need to define some terms: plasmon,

polariton and surface plasmon. First, a plasmon is the quasiparticle resulting from the

quantization of plasma oscillations. They are collective oscillations of the free electron

gas. If this collective oscillation happens at the surface of metal, it is called a surface

plasmon. Therefore, we define the surface plasmon as a collective oscillation of free

electrons at the interface of metal and insulator [8]. The surface plasmon is also called the

surface plasmon polariton. A polariton is the quasiparticle resulting from strong coupling

of electromagnetic waves with an electric or magnetic dipole-carrying excitation.

Therefore, if an electromagnetic wave excites the surface plasmons on a metal surface

and is coupled with the surface plasmon, it is called the surface plasmon polariton.

Dispersion Relation of Surface Plasmon

To get the dispersion relation for surface plasmons [8, 34, 40], we need to consider

an interface between two semi-infinite isotropic media with dielectric functions, P1 and 82.









The x and y axes are on a plane of the interface and the z axis is perpendicular to the

interface. Medium 1 dielectricc function 1e) and medium 2 dielectricc function 82) occupy

each half of the space, z > 0 and z < 0, respectively. The electromagnetic fields for the

surface wave which propagate in the x direction and are confined in the z direction on this

interface are of the form:

E, = E>e )-t) e-a1 z > 0 (2-5)

E, = Eo
where E> and E< are electromagnetic fields in each half space, Eo> and Eo< are amplitudes,

co is angular frequency, t is time, kx is the wave vector of surface wave propagating along

the x-axis and al, a2 are positive real quantities.

Dispersion relation for the p-polarization

For p-polarized electromagnetic wave (TM wave), the magnetic field is

perpendicular to the plane of incidence and the electric field is in the plane of incidence.

In Figure 2-1, the H-field is along the y-axis and the E-field is in the x-z plane. Thus, the

E and H fields in each region can be expressed as

E= (A, 0, B)ey(kx-t)e z > 0 (2-7)

H =(0, C, O)e'(k-x-t)e- z > 0 (2-8)

E2 (D, 0, E)e'(kx )t)e'a2 z <0 (2-9)

H2 = (0, F, 0)e' -'t)e"2 z <0 (2-10)

The boundary condition that needs to be considered is that the components of E

and H parallel to the surface are continuous at the interface, z = 0, that is

El = E2xlz (2-11)










Hix =0 H 2xz0 (2-12)

Substituting Eq. (2-7) through Eq. (2-10) into Eq. (2-11) and Eq. (2-12), the boundary

conditions give A = D and C = F. One of the Maxwell's equations for continuous media

is

E aE
Vx H (2-13)
c 8t

For region 1 and 2, the x components in Eq. (2-13) give


aC= io A z>0 (2-14)
c


aF = -icoi D z <0 (2-15)
c

With A = D and C = F, division of Eq. (2-14) by Eq. (2-15) gives

= 1 (2-16)
a'2 2

This equation is a condition for the surface plasmon mode and demonstrates that one of

the two dielectric functions must be negative, so that, for example, the interface of

metal/vacuum or metal/dielectric supports the surface plasmon mode.

To get the dispersion relation of the surface plasmon, we use two Maxwell's

equations:

E dE
VxH = (2-13)
c 8t

1 8H
VxE=- (2-17)
c 8t

Operating V x on both sides of Eq. (2-17) and substituting for V x H from Eq. (2-14)

gives










I a E 2 2E
Vx(Vx E) = (V x H) = (2-18)
c at C2 Qt2

Using V x (V x E) = V(V. E)- V E and V E = 0 for a transverse wave, we get the

transverse wave equation:


V2E = (2-19)
C at2

In the region ofz > 0, the x and z components of the solution of Eq. (2-19) are


x-component: az2A+acikB= 2 2A (2-20)



z-component: azikxA- kZB = c--2B (2-21)
c

Combining Eq. (2-20) and (2-21), we get

x 1 1 2
-kx+a 2 z >0 (2-22)
c

Similarly, in the region ofz < 0:


81 2
-k2+a =--c- z<0 (2-23)


Combining Eqs. (2-16), (2-22), and (2-23) we obtain the dispersion relation of the surface

plasmon:


kx= Dispersion relation of surface plasmon (2-24)
C 8 +82

Dispersion relation for the s-polarization

As shown in Figure 2-2, the s-polarization has the E field perpendicular to the plane

of incidence and the H field in the plane of incidence. Then, we have a set of E and H

fields:









E1 =(O,A, O)e' -c)e- z > 0 (2-25)

Hi = (B, 0, C)e -c)e- z >0 (2-26)

E2 = (0, D, 0)e "-t)e"2 z <0 (2-27)

H2 =(E, 0,F)e' -o)eC2 z <0 (2-28)

As in the p-polarization case, we apply the boundary conditions Eqs. (2-11) and (2-

12) and get A = D and B = E. Then we use the Maxwell's equation:

1 dH
Vx E (2-29)
c at

Solving Eq. (2-29) with Eq. (2-25) through Eq. (2-28) for both regions ofz > 0 and z < 0

give solutions with x and z components for each region:


x-component: B= A > 0 (2-30)
io)

ke
z-component: C = kc A z > 0 (2-31)
ca


x-component: E= 2 D z <0 (2-32)
io)


z-component: F = kx D z <0 (2-33)
0)

With the results from the boundary conditions, A = D and B = E, Eqs. (2-30) through (2-

33) can be combined and simplified


c (al +a2)A= 0 (2-34)
i')

Since we defined a1 and a2 positive, thus A = 0 and all other constants (B, C, D, E, and F)

also become zero. Therefore, the surface plasmon mode does not exist for the s-

polarization.






12


Z




E H
| ko
0
E Ez
Dielectric E1



Figure 2-1. Schematic diagram for p-polarized (TM) light incident on a dielectric/metal
interface

Z




H E
| ko
H Hz
Dielectric E1



Figure 2-2. Schematic diagram for s-polarized (TE) light incident on a dielectric/metal
interface
Dispersion curves
Figure 2-3 shows the dispersion curves of surface plasmons at the interface of

metal/air, metal/quartz and the light lines in vacuum and fused silica glass, respectively.

The momentum k is calculated by Eq. (2-24). The dielectric constant of metal, E2, in the

Eq. (2-24) is described by the Drude dielectric function [41]:











2 2 2
02 A2
P


(2-35)


where Ap is the bulk plasma wavelength of the metal (cop is the bulk plasma frequency). Ap

is 324 nm for the silver film used in this experiment. The dielectric constants of air and

fused silica substrate are 1.0 and 2.0, respectively.

In Figure 2-3, the thickness of the metal film is considered to be infinite; thus, the

interaction of the surface plasmons on both interfaces is ignored. But if the thickness is

finite, then there will be an interaction between two surface plasmons which will distort

the dispersion curves of surface plasmons [34]

light in air

5x10' 1 I I II
S--- light in quartz

4x10 -
4x 1" -- SP at air/metal



3x10o SP at quartz/meta[



32x10



1x10' -




0.0 5 0x10 1.0x10l1 1.5x10' 2 0x10'" 2.5x10'1 3.0x101

ck(s-')
Figure 2-3. Dispersion curves of surface plasmon at air/metal interface and at
quartz/metal interface, light lines in air and fused silica









Propagation Length of the Surface Plasmon

The propagation length of the surface plasmon can be defined by the imaginary part

of the wave vector k, in Eq. (2-24) as follows [8, 34, 40]


L (2-36)
2k,

The dielectric function E2 is a function of co. At each co, it is a complex number,

E2 = ,2r + iE2 where e- and E2, are the real and the imaginary parts of the dielectric

function. The wave vector kx is also a complex number, kx = k.r + ik .


kx, = -I2r2 1 (2-37)



k = 2 2 (2-38)
C E + E 2Er

From Eqs. (2-30) and (2-32), we can get the propagation length of the surface plasmon:


Lc 2r (2-39)
0 1 +2rJ E2

Using parameters for silver [42], we can evaluate the propagation lengths at air/silver

interface are about 20 ptm and 500 pm for X = 500 nm and X = 1 pm, respectively.

Surface Plasmon Excitation

As seen above, light does not couple to the surface plasmon on metal surface due to

no crossing point between the dispersion curves of the incident light and the surface

plasmon except for k = 0. There are two ways to excite the surface plasmon optically on

an interface of a dielectric and a metal. First, one can use a dielectric prism to make

coupling between the incident photons and the surface plasmon on an interface between

the prism and the metal [8]. But this is not a case which is studying in this dissertation, so









I am going to skip this part. Second, one can use periodic structures on the metal surface.

When light is incident on the grating surface, the incident light is scattered by the grating

structure. The surface component of the scattered light gets an additional "momentum"

from the periodic grating structure. This additional momentum enables the surface

component of the scattered light to excite the surface plasmon on metal surface.

Z


Photon, ko
On



Air E,


Metal E n ao


Surface plasmon, ksp

LZZI


t photon Scattered photon
o)=ck I


./1


I / Surface plasmon
co s p ......................./ ......... ....................................






I
ko ksp kx
(b)

Figure 2-4. Schematic diagrams of (a) the excitation of the surface plasmon by the
incident photon on a metallic grating surface and (b) the dispersion curves of
the incident photon, the scattered photon and the surface plasmon


Sx









Let us consider this case for one dimensional grating, as shown in Figure 2-4 (a).

When light with a wave number ko is incident on a periodic gating on a metal surface

with an incident angle 00, the incident light excites the surface plasmon on the metal

surface. The momentum conservation equation allows this surface plasmon to have a

wave vector, kp, equal to a sum of the x-component of the incident wave vector and an

additional wave vector which is the Bragg vector associated with the period of the

structure:


k = ko sin00 +m ko= (2-40)
ao c

where ko is the wave number of the incident light, and ao is the period of the grating

structure, and m is an integer.

As shown in Figure 2-4 (b), this additional wave vector shifts the dispersion line of

the incident light to the dispersion line of the diffracted photon. This light line crosses the

dispersion curve of the surface plasmon. This crossing means that the incident light

couples with the surface plasmon on the metal grating surface.

If we consider a two dimensional grating on the metal surface, as shown in Figure

2-5, the momentum conservation equation becomes


kp =k +k +igx +jg, g g =2" (2-41)
ao

where kx and ky are surface components of the incident wave vector, gx and gy are the

Bragg vectors, ao is a period of the grating, i andj are intergers. From Eqs. (2-24) and (2-

41), we get an equation which predicts the resonant coupling wavelengths of the incident

light and the surface plasmon on metallic grating surface. Putting k- = k in Eq. (2-24),


we get an equation:










S= 2- i sino, +(i2+j2) d dm _J2 sin20 (2-42)
S+j Ed + Em

From this equation, one can predict the wavelength where the incident light excites the

surface plasmon on the metallic grating surface.

The surface plasmon excitation wavelength is used to explain the enhanced

transmission phenomenon of the sub-wavelength hole array because the excitation

wavelengths are close to the wavelength of the enhanced transmission [7]. But the surface

plasmon excitation wavelength shows a 15 % difference between theoretical calculation

and experimental measurement [9].

Mechanism of Transmission via Surface Plasmon Coupling in Periodic Hole Array

As we mentioned, the surface plasmon is a collective excitation of the electrons at

the interface between metal and insulator. This surface plasmon can couple to photons

incident on the interface of metal and insulator if there exists a periodic grating structure

on the metal surface. So, the coupling between photon and surface plasmon forms the

surface plasmon modes on the interface. If both sides of metal film have the same

periodic structure, such as an array of holes, the surface plasmon modes on the input and

exit sides couple and transfer energy from the input side to the exit side. The surface

plasmon modes on the exit side decouple the photons for re-emission. In this optical

transmission process, the energy transfer by the resonant coupling of surface plasmon on

the two sides is a tunneling process through the sub-wavelength apertures. Thus, the

intensity of transmitted light decays with a film thickness exponentially.

To compensate this decay, a localized surface plasmon (LSP) [43-46] plays a role

in this process. The LSP is a dipole moment formed on the edges of a single aperture due





















Figure 2-5 Schematic diagrams of the excitation of the surface plasmon by the incident
photon on a two dimensional metallic grating surface
Photon


Metal


SSPin
(1)... .


101


SPout
Photon


Figure 2-6. Schematic diagram of transmission mechanism in a sub-wavelength hole
array. (1) excitation of surface plasmon by the incident photon on the front
surface (2) resonant coupling of surface plasmons of the front and back
surfaces (3) re-emission of photon from surface plasmon on the back surface









to an electromagnetic field near the aperture and it depends mainly on the geometrical

parameters of each hole. The LSP makes a very high electromagnetic field in the aperture

and increases the probability of transmission of the incident light.

CDEW (Composite Diffractive Evanescent Wave)

A recently proposed theory competing with the surface plasmon theory is the

CDEW [9, 47-49]. The CDEW is a second model explaining the enhanced transmission

phenomenon of sub-wavelength periodic structures.

Basic Picture of the CDEW

The CDEW model originates from the scalar near-field diffraction. Kowarz [50]

has explained that an electromagnetic wave diffracted by a two dimensional structure can

be separated into two contributions: a radiative (homogeneous) and an evanescent

inhomogeneouss) contributions. The diffracted wave equation for the 2-D structure is

based on the solution to the 2-D Helmoltz equation:

(V2 + k2)E(x, z) = 0 (2-43)

a2 a2 2r
where V2 + ,k = and E(x, z) = Eoe kz),the amplitude of the wave
2x -y A

propagating in the x, z directions. As mentioned, the diffracted wave is a sum of the

radiative (homogeneous) and the evanescent inhomogeneouss) contributions:

E(x, z) = Er (x, z) + E, (x, z) (2-44)

We note that the homogeneous and the evanescent components separately satisfy the

Helmoltz equation.

If we consider that the incident plane wave with a wave vector ko impinges on a

single slit of width d in an opaque screen, as shown in Figure 2-7 (a), the momentum

conservation of the incident wave and the diffracted wave should satisfy








k = 2- k2 (2-45)

where kx and k, are the wave vectors of the diffracted wave in the x and z directions. If kx

is real and if kx > ko, then

k = i k2 (2-46)

This result means that the diffractive wave propagates in the x direction while being

confined and evanescent in z direction. This evanescent mode of the diffracted wave

emerging from the aperture grows as d/ becomes smaller. In contrast, for kx < k, kz

remains a real quantity and the light is diffracted into a continuum of the radiative,

homogeneous mode. In Figure 2-7, the diffraction by an aperture is described in real

space (a) and k-space (b). The blue lines represent the radiative modes (kx < k0), whereas

the red lines represent the evanescent mode (kx > k ). The surface plasmon mode in this

picture is the green line which is one of the evanescent modes diffracted by the aperture.

Now, in order to find the specific solutions for the radiative and evanescent modes,

we need to solve Eq. (2-43). The solution for Eev at the z = 0 is

Ee, (x,0)= E Si ko x+ Si k0 x -- for x >- (2-47)


E (x, 0)= E Si kox+d +Sil kx x- for x < (2-48)

8 sin2 t
where Eo is the amplitude of the incident plane wave and Si(/Y) ol tdt.

If we consider the surface wave on the metal, Eq. (2-47) can be simplified with a

good approximation as [9]









E, d i
Eev -cos(k x+-) (2-49)
Zx 2

From the expression of CDEW in Eq. (2-49), we notice that the amplitude of the

CDEW decreases as 1/x with the lateral distance, x, and its phase is shifted by 7r/2 from

the propagating wave at the center of the slit. These results are different from the surface

plasmon. The phase of the surface plasmon is equal to that of the incident wave and its

amplitude is constant if absorption is not considered [9] Figure 2-8 shows the lateral field

profile of CDEW.



(a) z

k < Iko[ jacadiave modes
Ikol ...........






kx > Ikol evanescent modes

=i A2 2

(b) ", o =ck ,,SP



kx< Ikol k > jk










Figure 2-7 Geometry of optical scattering by a hole in a real screen in (a) real space and
(b) k-space for a range that k, is close to zero [9].










2

1.5



0.1


-4 -2 2 4
-0.5 xld
-d/2 d/2
-1

-1.5

-2

Figure 2-8. CDEW lateral field profile at z = 0 boundary, a plot of Eq. (2-44) [47]

CDEW for an Aperture with Periodic Corrugation

So far we have been discussing the diffraction by a single aperture. Now we are

going to extend our discussion to the periodic corrugation around a single aperture as

shown in Figure 2-9. The corrugations are on both input and output surfaces and actually

play a role as CDEW generating points. The individual corrugation also becomes a

radiating source.

As shown in Figure 2-9, when a plane wave impinges on the periodically

corrugated input surface with an aperture at the center, only a small part of the incident

light is directly transmitted through the aperture. Of the rest, part of incident light is

directly reflected by the metal surface and part of the incident light is scattered by the

corrugations. This scattering produces CDEWs on the input surface (red arrows). The

CDEWs propagate on the input surface and are scattered by the corrugations. The









corrugations on the input surface act as point sources for the scattered light which is

radiating back to the space. Part of the CDEWs propagating on the input surface is

scattered at the aperture and transmitted to the output surface along with the light directly

transmitted through the aperture. When the transmitted light (directly transmitted light

and CDEWs) arrives at the output surface, a small part of the light radiates directly into

space and the rest of the light is scattered again by the aperture and corrugations on the

output surface. The output surface CDEWs are now produced by the scattering of the

transmitted light and it propagates on the output surface between the aperture and the

corrugations. These propagating CDEWs on the output surface are scattered again by the

corrugations and radiated into the front space. This means that the each corrugation on

the output surface also becomes a radiation source. Thus, the transmitted light can be

observed from all over the corrugation structure at the near field. At the far field, the

radiation from the corrugations and the transmitted light from the aperture are superposed

and interfere with each other. As discussed before, the CDEW has 7t/2-phase difference

from the transmitted light. Therefore, the CDEWs and the directly transmitted light make

an interference pattern. The interference pattern of these two waves at the far field has

been observed experimentally. [49]

CDEW for a Periodic Sub-Wavelength Hole Array

Now we are going to develop the CDEW model for a periodic array of sub-

wavelength holes. The CDEW model for the periodic hole array is similar to that of an

aperture with periodic corrugations, except there are many holes rather than one.

As shown in Figure 2-10, a plane wave is incident on the input surface of a periodic

hole array. The incident wave is partially reflected, diffracted, and transmitted. The












I


I


I


I


I


Transmitted wave
Scattered wave
>- CDEWs
Scattered wave
Reflected wave
Incident plane wave


Figure 2-9.CDEW picture for an aperture with periodic corrugations on the input and
output surfaces. Red arrows indicate the CDEWs generated on the input and
output surfaces.

Transmitted wave


S:: Scattered wa
CDEWs
Scattered wE
, Reflected we


I


I


I


I


I


ive


ive
ive


Incident plane wave


Figure 2-10. A CDEW picture for a periodic sub-wavelength hole array. Red arrows
indicate the CDEWs generated on the input and output surfaces.









reflected wave consists of a direct reflection by the metal surface and the back scattering

from the hole, similar to the case of the hole with corrugations in the previous section.

Like the corrugations in Figure 2-9, each hole acts as a point for scattering and radiation

of the CDEWs on the input surface. The CDEWs on the input surface are partially

scattered back to space and partially transmitted along with the directly transmitted wave

through the holes to the output surface. Thus, the transmitted wave is a superposition of

the CDEW and the wave directly transmitted through the holes. When the transmitted

light arrives at the output surface, it is partially scattered (generates CDEWs on the

output surface) and partially radiated into space. The CDEWs generated on the output

surface propagate on the surface, and are partially scattered and radiated into space. In the

front space, the directly transmitted wave from the holes and the radiation from the

CDEWs are superposed to be the total transmission of the hole array for detection at the

far field observation point.

Fano Profile Analysis

Genet et al. [13] proposed that the Fano line shape in transmittance of periodic sub-

wavelength hole arrays is a strong evidence of an interference between a resonant and a

non-resonant processes. Figure 2-11 shows schematic diagrams for the coupling of the

resonant and non-resonant processes in a hole array. In Figure 2-11, the period of hole

array is ao, the thickness is h and the hole radius is r. As shown in this figure, there are

two different scattering channels: one open channel q1 corresponding to the continuum of

states and one closed channel q2 with a resonant state which is coupled to the open

channel with is called "direct" or "non-resonant" scattering process. The other possible

transition is that the input state transits to the resonant state (sometimes called

quasibound state) of the closed channel and then couples to the open channel via the









coupling term V. This is called "resonant" scattering process meaning opposed to the first

one. The "non-resonant" scattering process simply means the direct scattering of the

input wave by the sub-wavelength hole array. This scattering can be called Bethe's

contribution. Bethe's contribution is the direct transmission through the holes in the array

which is proportional to (d/ )4 and will be detected as a background in transmttance. In

contrast, the "resonant" scattering process is a contribution from the surface plasmon

excitation. This resonant scattering process basically consists of two steps: (1) the

excitation of the surface plasmon on the periodic structure of metal surface by the input

wave and (2) the scattering of the surface plasmon wave by the periodic structure. The

surface plasmon wave can be scattered into free space (reflection) or into the holes in the

array (transmission). A simple transmission diagram of this model can be described via

Figure 2-12. The total transmission amplitude is decided with the interference of the non-

resonant contribution (Bethe's contribution) and the resonant contribution (surface

plasmon contribution).

A paper published by Sarrazin et al. [12] has also discussed the Fano profile

analysis and the interference of resonant and non-resonant processes. In Figure 2-13, the

homogeneous input wave (i) incident on the diffraction element A is diffracted and

generates a non-homogeneous resonant diffraction wave (e) which is characterized by the

resonance wavelength, X,. This resonant wave (e) is diffracted by the diffraction element

B and makes a contribution to the homogeneous zero diffraction order. On the other hand,

the other input wave is incident on the diffraction element B and generates a non-resonant

homogeneous zero diffraction order. This non-resonant scattered wave from B interferes

with the resonant wave of X, from A. The Fano profile in transmittance of the sub-








wavelength hole array results from a superposition of the resonant and the non-resonant
scattering processes.


rcflcction
t


transmission


-X


Y


Figure 2-11. Schematic diagrams for Fano profile analysis. (a) Formal representation of
the Fano model for coupled channels and (b) physical picture of the scattering
process through the hole array directly (straight arrows) or via SP excitation
[13]


~I


ma


rJ
MI


Figure 2-12. A schematic diagram of the non-resonant transmission (Bethe's
contribution) and the resonant transmission (surface plasmon contribution)
[14]


a V2


C--


k-,

D]


t aSat
Ldwri W













Interference between
resonant and nonresonant
processes tn.


Resonant profile


Figure 2-13. Schematic diagram of the interference between the resonant and non-
resonant diffraction in transmission of sub-wavelength hole array [12]














CHAPTER 3
INSTRUMENTATION

Optical transmittance measurements have been taken using two spectrometers: a

Perkin-Elmer 16U monochromatic spectrometer and a Bruker 113v fourier transform

infrared (FTIR) spectrometer. The Perkin-Elmer 16U monochromatic spectrometer was

used for the wavelength range from ultraviolet (UV), throughout visible (VIS) and to

near-infrared (NIR), i.e., between 0.25 [m and 3.3 [m. Measurement for longer

wavelengths (> 2.5 [am) employed the Bruker 113v FTIR spectrometer. The FTIR

spectrometer is able to measure up to 500 [m, but in this experiment it was used for a

range between 2.5 [m and 25 [m, i.e., near-infrared (NIR) and mid-infrared (MIR).

Perkin-Elmer 16U Monochromatic Spectrometer

A spectrometer is an apparatus designed to measure the distribution of radiation in

a particular wavelength region. The Perkin-Elmer 16U monochromatic spectrometer

consists of three principal parts; light source, monochromator and detector. Figure 3-1

shows a schematic diagram of the Perkin-Elmer 16U monochromatic spectrometer. Here,

the spectrometer has three light sources, two detectors and a gating monochromator.

Light Sources and Detectors

This spectrometer has three different light sources installed: a tungsten lamp, a

deuterium lamp and a glowbar. The tungsten lamp is for VIS and NIR (0.5 [am 3.3 [am),

and the deuterium lamp is for VIS and UV (0.2 [am 0.6 am). This spectrometer has the

glowbar for MIR region, but it was not used because the matching detector for MIR

region has not been installed. This monochromatic spectrometer has two detectors: a lead









sulfide (PbS) detector for VIS and NIR range (0.5 C[m 3.3 km) and a Si photo

conductive detector (Hamamatsu 576) for UV and VIS range (0.2 [m 0.6 km).


Figure 3-1. Schematic diagram of Perkin-Elmer 16U monochromatic spectrometer

Grating Monochromator

A monochromator is an optical device that transmits a selectable narrow band of

wavelengths of light chosen from a broad range of wavelengths of input light.









Monochromators usually use a prism or a grating as a dispersive element. In prism

monochromators, the optical dispersion phenomenon of a prism is used to separate

spatially the wavelengths of light, whereas the optical diffraction phenomenon of grating

is used in the grating monochromators for the same purpose. In this section, only the

grating monochromator will be discussed.

Monochromator configuration

There are several kinds of monochromator configurations. The configuration of

monochromator which is used in Perkin-Elmer 16U spectrometer is the Littrow

configuration. A schematic diagram of the Littrow configuration is shown in Figure 3-2.



Slit B


MirrorA

SlitA Mirror B



Grating

Figure 3-2. Schematic diagram of the Littrow configuration in the monochromator of
Perkin-Elmer 16U spectrometer

In this configuration, the broad-band light enters the monochromator through slit A,

which is the entrance slit. This entrance slit controls the amount of light which is

available for measurement and the width of the source image. The light that enters

through the entrance slit (slit A) is collimated by mirror A, which is a parabolic mirror.

The collimated light is such that all of the rays are parallel and focused at infinity. The

collimated light is diffracted from the grating and collected again by the parabolic mirror









(mirror A) to be refocused. The light is then reflected by the plane mirror (mirror B), and

sent to the exit slit (slit B). At the exit slit, the wavelengths of light are spread out and

focus their own images of the entrance slit at different positions on the plane of exit slit.

The light passing through the exit slit contains an image of the entrance slit with the

selected wavelength and the part of the image with the nearby wavelengths. Rotation of

the grating controls the wavelength of light which can pass through the exit slit. The

widths of the entrance and exit slits can be simultaneously controlled to adjust the

illumination strength. When the illumination strength of the input light becomes stronger,

the signal to noise (S/N) ratio becomes higher but, at the same time, the resolution of

measurement becomes lower because the exit slit opens wider and passes a broader band

of the light.

Resolution of monochromator

One of the important optical quantities of monochromator is its resolution. The

resolution of monochromator in the Littrow configuration (a = = 0) can be expressed as

[51]

R -- (3-1)
AA (1 R) + (1 Rg)


R, = (3-2)
2f


Rg (3-3)
h(a)

where R, is the resolving power contributed from optical quantities of all components

except for the grating, Rg is the ultimate resolving power of the grating, S is the slit width,

0 is the angle of incidence and diffraction,f is the focal length of collimating mirror, h(a)









is an error function, and Ro is the resolving power of the grating. Thus, the resolution of

monochromator is dependent not only on the grating but also on other optical and

geometrical quantities of the monochromator.

The Diffraction Grating

A diffraction grating is one of the dispersing elements which are used to spread out

the broad band of light and spatially separate the wavelengths.

Grating equation and diffraction orders

Figure 3-3 shows the conventional diagram for a reflection grating. In this Figure,

the general equation of grating can be expressed as [52]

Path difference = PQ + QR

d sin a + d sin =mA (3-4)

where m is diffraction order which is 0, +1, +2 ....

diffracted
incident zero order




P

R

d Q

Figure 3-3. Schematic diagram of a reflection grating.

Iff/ = -a, m becomes zero, the zero order diffraction. When the diffraction angle fl

is on the left-side of the zero order angle, the diffraction orders are all positive, m > 0,

whereas if the angle fl crosses over the zero order and is on the right side of the zero order,

the diffraction order m becomes negative, m < 0.









Blaze angle of the grating

Most modern gratings have a saw-tooth profile with one side longer than the other

as shown in Figure 3-4. The angle made by a groove's longer side and the plane of the

grating is the blaze angle. The purpose of this blaze angle is so that, by controlling the

blaze angle, the diffracted light is concentrated to a specific region of the spectrum,

increasing the efficiency of the grating.

grating normal
facet normal diffracted
incident zero order







d
4 blaze angle


Figure 3-4. Schematic diagram of a blazed grating

Resolving power of grating

As mentioned before, the resolving power of a grating is one of the important

optical quantities contributing in the resolution of monochromator. If we use the Rayleigh

criterion, the resolving power of grating becomes


R= = mN = (sina + sin ) (3-5)
AA A

where Nis the total number of grooves on the grating, Wis the physical width of the

grating, 2 is the central wavelength of the spectral line to be resolved, a and /f are the

angles of incidence and diffraction, respectively. Consequently, the resolving power of









grating is dependent on the width of grating, the center wavelength to be resolved, and

the geometry of the optical setup.

Bruker 113v Fourier Transform Infrared (FTIR) Spectrometer

As mentioned before, the Bruker 113v FTIR spectrometer was used to measure

transmission in the range of MIR (2.5 am 25 r[m). Basically, this FTIR spectrometer

can cover up to the range of far-infrared (FIR) which is up to 500 am. The entire system

is evacuated to avoid absorption of H20 and CO2 for all of the measurements.

Interferometer

The interferometer is the most important part in FTIR spectrometer. The

interferometer in a FTIR spectrometer is a Michelson interferometer with a movable

mirror. The Michelson interferometer is shown in Figure 3-6.

The electric field from the source can be expressed as

E() = Eoek-x (3-6)

where 2 is a position vector, k is a wave vector and Eo is an amplitude of the electric

field. As shown in Figure 3-6, 11, 12, 1s and 12+x/2 are the distances between the source

and the beam splitter, the beam splitter and the fixed mirror, the beam splitter and the

detector, and the beam splitter and the movable mirror, respectively. The reflection and

transmission coefficients of the beam splitter are rb and tb, and the reflection coefficients

and the phases of the fixed mirror and the movable mirror are rf, pf and rm, P9m,

respectively.

The electric field Ed which arrives at the detector consists of two electric field

components: one from the fixed mirror, Ef, and the other from the movable mirror, Em.






36

fixed mirror



I movable mirror
source
1 12,+X/2
I r tb

beam splitter"





Detector


Figure 3-5. Schematic diagram of Michelson interferometer

Thus, Ed, Ef, and Em are

Ed = E + Em (3-7)


Ef = Eoe'kl rbk rfek2 e'ki2eftb ekl3 (3-8)

Em = Eoe'kl tb ek(12+x/2) +x/2) e rme'2 e rbe 'kl3 (3-9)

To simplify, consider the mirrors as perfect mirrors, so rfand rm are 1. Also, we define

the frequency v as follows

2xyv 27c
k= = -o) (3-10)
c A

With c = 1, Eq. (3-10) becomes 2irv = c) and we measure x in cm and v in cm-1. If we let

(o()) = (P ,(f q =( k( + 22 +/3)+(~

Ed = Eo rbtb e' (1 +(+))) (3-11)

The light intensity at the detector is









Sd =EdE, = 2SRbTb[1 + cos( oix + P(o(o))] (3-12)

where So = EoEo, Rb and Tb are the reflectance and the transmittance of the beam splitter.

Sd is the intensity of light at the detector for a given frequency co. Then the total

intensity for all frequencies is

Id(x) = J Sd (o)do = 2J SORbb [1 + cos(cx + ((w))]doe (3-13)

For an ideal beam splitter, Tb = 1 Rb and RbTb with Rb = 1/2 is


RbTb =Rb(1-Rb) = (3-14)
4

Here we define the beam splitter efficiency, Eb, as follows

eb -4RbTb = 4Rb(1-Rb) (3-15)

Then, Eq. (3-13) becomes


Id (x)=- = SO (C)) (C)[1 + cos(Cx + p(*))])dt (3-16)

Here we have two special cases, x oo and x = 0. For x oo, Id in Eq. (3-17)

becomes Id (oo) called the average value:


Id (0o)= f SO (C)b(m)da (3-17)
20

With x = 0 and p (co) = 0 (zero path difference or ZPD), Id becomes Id (0) called the white

light value:

Id(0) = J So (o)Eb (c)do = 2Id (o) (3-18)

Now we need to define another quantity which is the difference between the intensity at

each point and the average value called the interferogram:

(x) Id () = S() cos(cx + (pw(o))do) (3-19)









where S(o) So(wc)Eb(co) and y(x) is the cosine Fourier Transform of S(c). If we assume

that S(c) is hermitian, then y(x) is


y(x) = 4 JS(c4)eO(w)e"tdc (3-20)
4-

and


S(O)eO(O=) j2 (x)e ,-dx (3-21)


From the measurement with the interferometer, we get the interferogram, y(x) and

compute the Fourier transform to get the spectrum, S(o).

The resolution of a Fourier spectrometer consists of two terms: one contributed

from the source and the collimation mirror and the other decided by the maximum path

difference.

1 1 1
-+ (3-22)
R R, R2


8f2
R, (3-23)


R2 =lv (3-24)

wherefis the focal length of the collimating mirror, h is the diameter of the circular

source, / is the maximum path difference or the scan length and v is the wave number in
-1
cm.

Description of FTIR Spectrometer System

A simple description of interferometer of the FTIR spectrometer is as follows. The

light from a source is focused on a beam splitter after reflected by a collimation mirror.

This beam splitter divides the input light into two beams: one reflected and the other

transmitted. Both beams are collimated by two identical spherical mirrors to be sent to a










two-sided moving mirror. The moving mirror reflects both beams back to the beam

splitter to be recombined and the recombined beam is sent to the sample chamber for

measurement.




















I Source Chamber III Sample Chamber
a Near- mkd- or far- IR sourwsw i Trwaritatne focum
b Automated Aperture I Rertlance focus
II Irterferometer Chamber IV Detecor Chamber
c Opbcal filter k Near-. rd-. or ar-IR
d Automabc beamsplier changer detector
e Two-side movable mror
f ContrWo i fromater
g Reference aser
h Remole control algnment rmnor

Figure 3-6. Schematic diagram of the Bruker 113v FTIR spectrometer

As shown in Figure 3-6, the Bruker 113v FTIR spectrometer consists of 4 main

chambers: a source chamber, an interferometer chamber, a sample chamber and a

detector chamber. In the source chamber, there are two light sources: a mercury arc lamp

for FIR (500 [m 15 [m) and a glowbar source for MIR (25 [m 2 am). The

interferometer chamber has actually two interferometers for a white light source and a

helium-neon (He-Ne) laser. As we know the exact wavelength of the laser, the small

interferometer with the He-Ne laser is used as a reference to mark the zero-crossings of

its interference pattern which defines the positions where the interferogram is sampled.

This is the process of digitization of interferogram.






40


White light transmission and reflection are measured in the sample chamber. The

transmission is measured in the front side of the sample chamber and the reflection is

measured in the back. There are two detectors installed in the detector chamber: a liquid

helium cooled silicon bolometer and a room temperature pyroelectric deuterated

triglycine sulfate (DTGS) detector. The bolometer detects light signals in the FIR range

(2 am 20 km) and the DTGS detector is for MIR (2 km 25 km).














CHAPTER 4
SAMPLE AND MEASUREMENT

Sample Preparation

The sub-wavelength periodic array samples were prepared using electron-beam

lithography and dry etching. The sample fabrication process is simply described as

follows. Silver films with thickness between 50 nm and 100 nm were deposited on

substrates using thermal evaporation. Fused silica and ZnSe were used for the substrates.

Before the E-beam writing process, a PMMA film is coated on the silver film. The

PMMA coated samples were baked on a hot plate at 180 OC for a minute. The baked

PMMA film was exposed by the electron beam to make a periodic pattern on it. After the

E-beam writing, the sample developed with the area of the PMMA film, which was not

exposed by the electron beam, removed by the developing solution. The patterned

PMMA film is going to be used to mask the silver film from the dry etching. During the

dry etching process, Ar-ions strike the surface of the sample to make holes on the silver

film. Finally, the remaining PMMA mask was removed with the stripping solution.

With this fabrication process, a variety of samples have been prepared for this

research, listed in Table 4-1. SEM images of the selected samples are also shown in

Figure 4-1.

Substrates

Fused silica and ZnSe were used for the substrates. When the enhanced

transmittance is expected to occur at wavelengths shorter than 5000 nm, fused silica

substrate is used. If the transmission peaks are supposed to occur at wavelengths longer







42
















tal 1 mn BIT 4W SidA *IrAm Oft 10 Fb 2004 IRit 1C t EIN. 4C W S4d A I.nL DOS AFe Nf
Magaot x K WD llrn UrN, reTRAINING T7_ 7It 2 ag5n 1m x [- I n 11 r U flrm TRMaING TirmN 11,50

(a) (b)

















RbiC Iu n ET' LwW SI Gi M4 ht. Oftfl n7 N RNu C lmC i, x MtB00W3 OW A*an IN-7J0W
M6 KX ----- IN-- 11In- Ur0 N-l rTRAINING -TiT rmK 11-.U-7 MN4- 20 uKX 3 3llm -rN =TRAINING TN n 13", 25

(c) (d)
















R I-, 5HW5 SW AhLO -C RfN Do,? J. 2M5 11AMW gMA-N Dal. J.2004
M.. 102 -li I.M 11., WWN-C RAn*,T0716 M t-94715 La-- ----- AM-11- NwN* R.CAINw TI- 10M21

(e) (f)

Figure 4-1. SEM images of periodic hole arrays samples. (a) A14-1, (b)A14-3, (c) A18-1,
(d) A18-2, (e) A18-3, and (f) A18-4









than 5000 nm, ZnSe substrate is used. It is because fused silica is transparent between

300 nm and 5000 nm, while ZnSe is transparent between 500 nm and 15000 nm [53].

Measurement Setup

We have used the Perkin-Elmer 16U monochromatic spectrometer and Bruker 113v

FTIR spectrometer for transmittance measurement. Transmittance of an open aperture

and of the sample has been measured. We first measured an open aperture as a reference

and then measured the sample. We used the same diameter aperture when measuring the

sample to keep the measurement area the same. Then we calculated the ratio of the

transmission of the sample to that of the open aperture to get the transmittance of the

sample.

Table 4-1. List of the periodic sub-wavelength hole arrays

film thickness
sample hole shape hole size (nm) period (nm) fm thkn
(nm)
A14-1 square 900 x 900 2000 70
A14-2 square 900 x 900 3000 70
900 x 900(out)
A14-3 square donut 00 x 900(out) 2000 70
500 x 500(in)
A15 square 500 x 500 1000 50
A18-1 square 840 x 840 2000 100
A18-2 rectangular 900 x 1300 2000 100
A18-3 slit 1000 (width) 2000 100
8-4 square on 2000 (x-axis) 100
rectangular grid 1500 (y-axis)

We measured transmittance as a function of the angle of incidence. The samples

were mounted on a transmission sample holder that allows changes in the angle of

incidence. A picture of the transmission sample holder is shown in Figure 4-2. By rotating

about an axis perpendicular to the direction of the incident light, the angle of incidence is

changed. We measured transmittance at every 2 degrees between 0 degrees and 20

degrees. Also, we have varied the in-plane azimuthal angle. The azimuthal angle can be









varied from 0 degrees to 360 degrees. We used this measurement to study the effect of

polarization direction. This angle can be controlled using the same transmission sample

holder by rotating the sample mounting plate shown in Figure 4-2.




Incident angle rotator








Azimuthal angle rotator


Sample mounting plate
(An open aperture at center)


Figure 4-2. Picture of the sample holder used to measure transmittance with changing the
angle of incidence and the in-plane azimuthal angle

After the exit slit of the monochromator of Perkin-Elmer 16U spectrometer, we

could installed one of three different polarizers. A wire grid polarizer that is made of gold

wires deposited on a silver bromide substrate is used for the MIR region, and two

dichroic polarizers are used for NIR, VIS and UV regions. We can get the either s-

polarized or p-polarized incident light by using these polarizers. Another wire grid

polarizer has been installed on the exit aperture of the interferometer chamber of the

Bruker 113v FTIR spectrometer to get polarized light in the MIR region. In the FTIR

spectrometer, the polarizer is rotated instead of the sample.






45


In the Perkin-Elmer spectrometer, an optical solid half angle of the incident light on

samples is adjustable with an iris aperture installed on the spherical mirror before the

transmission sample holder (see Figure 3-1), but for most of measurement, we set the iris

aperture to make this angle 1 o, to minimize the incident angle effect. The optical solid

half angle of the Bruker 113v spectrometer is about 8.5 and was not adjusted.

Once we measured the samples with both spectrometers, the two transmittance data

have been merged into one transmittance data by our own data merging program.














CHAPTER 5
EXPERIMENTAL RESULTS

In this chapter, we present our experimental results. These experimental results will

be shown as follows. First, we present experimental data for the transmittance of the

arrays of square holes. We discuss the dependence on the period of the hole arrays, and

also on the thickness of the metal films. Second, transmittance of the square hole array as

a function of the angle of incidence using polarized light is presented. Third,

transmittance with different hole shapes, hole sizes and in-plane polarization angles are

shown. Finally, transmittance with different dielectric materials interfaced to the metal

film is presented.

Enhanced Optical Transmission of Sub-wavelength Periodic Hole Array

Figure 5-1 shows the transmittance of square hole array (A14-1) between 300 nm

and 5000 nm. As shown in this figure, the transmittance maximum occurs at 3070 nm

which shows an intensity of 60 %. This is about 3 times greater than the fraction of open

area. This means that the light which is impinging not only on the hole area but also on

the metal surface transmits into the output surface of the hole array via a certain

transmission mechanism. This enhanced transmission of sub-wavelength hole array was

first reported by Ebessen et al. in 1998. [7] The reason why it is called "enhanced" is that

the transmittance intensity is not only greater than the fraction of open area but also much

greater than a prediction from the classical electromagnetic theory for transmission of an

isolated aperture proposed by Bethe in 1944 [2]. Other spectral features we see from this

transmittance are the second highest peak at 2450 nm and another sharp peak at 323 nm.









The sharp peak at 323 nm is the bulk plasmon peak of silver and this is an intrinsic

property of the metal which is silver.


1000 2000 3000 4000
Wavelength(nm)


5000


Figure 5-1. Transmittance of the square hole array (A14-1) and a silver film

Comparison of Enhanced Transmission with Classical Electromagnetic Theory

For comparison we need to recall the Bethe's transmittance for a single sub-

wavelength hole, Eq. (2-4):

A 64 (kD)4 T (2-4)
2- 2 18 =T (2-4)
D 2 27_ r 26 z

In Figure 5-2, we show the transmittance calculated with Eq. (2-4) for wavelengths

up to 5000 nm and compare with the transmittance measured with the square hole array.

As shown in Figure 5-2, Bethe's calculation is reasonable for wavelengths longer than

2000 nm which is 2 times greater than the dimension of hole. For wavelengths shorter










than 2000 nm, the calculated transmittance increases very rapidly and is not compatible

with the measured transmittance.

At 3070 nm the intensity of the transmittance maximum is 2.93, while the

transmission amplitude of Bethe's calculation at the same wavelength is 0.19. Thus, the

measured transmittance is 15 times greater than the calculated one at the wavelength of

the transmittance maximum.




Bethe
o measurement
CU


0


-N

0

S\ Open fraction






0 1000 2000 3000 4000 5000
Wavelength(nm)

Figure 5-2. Comparison between Bethe's calculation and the transmittance measured
with the square hole array (A14-1)

Dependence of Period, Film Thickness and Substrate on Transmission

The experimental data shows that the enhanced transmission of sub-wavelength

hole array depends on materials and geometrical parameters of sample. In this section, we

discuss the dependence on the period of the hole array, the film thickness and the

substrate material on transmission.









Dependence on Period of Hole Array

For this experiment we prepared two different hole array samples which have

different periods of 1 pm and 2 pm, respectively. These samples are fabricated on silver

film. The thicknesses are 50 nm for the 1 [pm period sample and 100 nm for the 2 tpm

period sample. The hole size for the 2 pm period sample is 1 pm x 1 pm and that of the 1

jpm period sample is 0.5 pm x 0.5 jpm. Both samples are prepared on fused silica

substrates.


1000 2000 3000 4000
Wavelength(nm)


5000


Figure 5-3. Transmittance of square hole arrays with periods of 1 pm (A15) and 2 pm
(A18-1)

Figure 5-3 shows the transmittance of both samples. The transmittance maxima for

1 pm and 2 pm period samples appear at 1560 nm and 2940 nm, respectively. The ratio

of the two peak positions is about 1.88. This is very close to 2 which is the ratio of the

periods of both samples. The second highest peaks are located at 1170 nm and 2180 nm.









The ratio of the second highest peak positions of both samples is 1.86 and it is almost the

same with that of the maximum peak positions. The transmittance minimum or the dip

more closely follows the ratio of the periods. The dip located between two highest peaks

occurs at k = 1410 nm for the 1000 nm period sample and at k = 2800 nm for the 2000

nm period sample. The ratio of dip positions is 1.98, almost same as the ratio of the

periods of the two samples. From this simple consideration we are able to predict that the

positions of peaks and dips in transmittance of sub-wavelength periodic hole arrays are

closely associated with the periods of hole arrays.

Dependence on the Thickness of Metal Film

Another feature in Figure 5-3 is the dependence of the transmittance on the

thickness of the metal film. As indicated in this figure, the thickness of the metal film in

the 1 [tm period array sample is 50 nm and that of the 2 [tm period array sample is 100

nm. Two transmittances from these hole arrays show different spectral behaviors. The

transmittance of the hole array with 50 nm thickness shows a stronger maximum peak, a

higher background, and a broader line-width compared to the transmittance of the hole

array with 100 nm thickness [55].

For a direct comparison between these hole array samples, we rescaled the x-axis to

wavelength divided by the period of each array. These rescaled transmittances are shown

in Figure 5-4. The background in the transmittance for the hole array with 1 [tm period is

higher than that of the hole array with 2 [tm period, due to the difference of thickness in

the metal film. For a thinner metal film, transmission through leakage paths in the film or

direct transmission through metal film increase. These kinds of contribution decrease

when the thickness of film increases. Thus, the background for the hole array with 2 tm







51


period decreases. The difference between the backgrounds of the 1 [m period hole array

and the 2 am period hole array is about 10 %.


1.0

0.9

0.8

0.7

0.6 -

0.5

0.4 -

0.3

0.2-

0.1 -

0.0 -
0.0


0.5 1.0 1.5 2.0


Figure 5-4. Transmittance vs. scaling variable, ks = k/(nd x period), for the square hole
arrays of 1 [m period (A15) and 2 [m period (A18-1) made on fused silica
substrates (nd = 1.4)

From Figure 5-4, we can see a shift of the transmittance maximum even though

these hole arrays are supposed to have the maximum at the same position in the rescaled

x-axis. And also the positions of the dips in the transmittance of 1 and 2 [m period hole

arrays do not coincide but are slightly different. This difference in position of peak or dip

might be attributed to an imperfection in the geometrical structure of the hole arrays. But,

if we take a closer look in the figure, the peak of the 1 am period array has a little broader

line-width than that of the 2 am period array. The broadness of transmission peak is

basically coming from factors such as a larger hole size and a thinner film which increase









the coupling strength between front and back surfaces. This coupling also probably

causes the shift in peak position.

Dependence on the Substrate Material

The transmittance of the hole arrays depends on the dielectric materials interfaced

with the hole array. In particularly, the positions of peaks and dips are strongly dependent

on the dielectric material. In order to see the effect of the dielectric material in

transmittance, we used two different substrates: fused silica and ZnSe. The dielectric

constants of fused silica and ZnSe are 2.0 and 6.0, and the transmittances of bare

substrates are 90 % and 70 %, respectively [53].

Figure 5-5 shows the transmittance of a 2 [m period square hole array (A14-1) on

different substrates: one on a fused silica substrate and the other on a ZnSe substrate.

Even though those samples are on different substrates, the film thickness of films was 70

nm for both transmittances. In Figure 5-5 (a), the hole array on fused silica has its

transmittance maximum at 3070 nm while the maximum for the array on ZnSe substrate

is at 5180 nm. The ratio of the peak positions of the two samples is about 1.69. We know

the refractive indices of fused silica and ZnSe which are 1.4 and 2.4, respectively, so that

nznse / nsio2 = 1.7, close to the ratio of the peak wavelengths. This result indicates that the

most dominant factor for this big red shift in the peak positions of these two hole arrays is

the refractive index of the substrate material. In Figure 5-5 (b), the x-axis is rescaled with

wavelength divided by a product of the refractive index and the period, ks = k / (nd x

period). Even though the effect of the period and the refractive index is eliminated by the

rescaling, the dip positions are still different between the two spectra. This is probably

due to imperfections of the samples such as a difference in the thickness or the period.


































0 1000 2000 3000 4000 5000 6000 7000 8000
Wavelength(nm)


0.0 L-
0_0


0-5 1-0 1.5
s


Figure 5-5. (a) Transmittance vs. wavelength (b) transmittance vs. scaling variable, ks =
X/(nd x period), for the square hole arrays of 2 pm period (A14-1) made on a
fused silica substrate (nd = 1.4) and a ZnSe substrate (nd = 2.4)










Dependence on the Angle of Incidence

In this section, we will discuss the effect of the incident angle on the transmittance.

For this measurement we used the square hole array with 2 pm period (A14). As

mentioned in chapter 4, the incident angle is changed by rotating about an axis

perpendicular to the incident light and the plane of incidence. For this measurement we

used polarizers to get the s- and p-polarized incident light. We also measured with nearly

unpolarized light. The transmittance was measured every 2 from 0 to 20




0.9
unpolarized
0.8 00 polarization

0.7 90 polarization

S0.6

S0.5 ,

04
I--
03

0.2

0.1

0.0 I I
2200 2400 2600 2800 3000 3200 3400
Wavelength(nm)


Figure 5-6. Transmittance of a square hole array (A14-1) with three different
polarizations at normal incidence

From this experiment, we found a very strong dependence of the transmittance on

the incident angle. In addition, a significant polarization dependence of the transmittance

at non-normal angle of incidence is also observed. The spectral behavior of transmittance

of s and p-polarized light differ when the incident angle is changed [14, 56, 57].









Figure 5-6 shows the normal incidence transmittance of a square hole array (A14-1)

for three different polarizations. These spectra are almost the same except for the second

highest peak. The intensity of the second peak for the case of unpolarization is a little

higher than the peaks of others. A reason of this similarity in transmittance at normal

incidence is that the sample (A14-1) used in this experiment has a geometrical symmetry

for the two orthogonal polarizations.

Figure 5-7 (a) shows schematically the s-polarized light incident on a hole array

sample. The lower panel, Figure 5-7 (b) shows the transmittance of a square hole array

(A14-1) with s-polarized incident light as a function of the incident angle. The s-

polarization (TE mode) has a transverse electric field which is perpendicular to the plane

of incidence. The magnetic field is in the plane of incidence. Figure 2-2 in Chapter 2

shows a schematic diagram for s-polarization.

In Figure 5-7 (b), we can see some dependence on the transmittance on the angle of

incidence. The intensity of the maximum transmission peak decreases and the line-width

of the peak increases when the incident angle increases. The locations of both the

maximum peak and of the dip shift to shorter wavelengths with increasing incident angle,

while the second highest peak shifts the longer wavelengths.

Figure 5-8 (a) shows a schematic diagram of p-polarized light incident on a hole

array. Figure 5-8 (b) shows the transmittance of the same square hole array using p-

polarized incident light as a function of the incident angle. The p-polarization (TM mode)

has a transverse magnetic field, perpendicular to the plane of incidence. The electric field

is in the plane of incidence. Figure 2-1 in Chapter 2 shows schematically the case of p-

polarization. For p-polarization, the transmittance is quite different from that of the s-







56


polarization as the incident angle changes. The maximum peak at 3070 nm at normal

incidence splits into two peaks. One peak shifts to the longer wavelengths while the other

peak shifts to the shorter wavelengths with increasing incident angle.


1.0

0.9

0.8

0.7

0.6

0.5
E
- 0.4

S0.3

0.2

0.1


0.0 1
220


0


k
/~


2400 2600 2800 3000 3200


3400


Wavelength(nm)
(b)

Figure 5-7. Measurement of transmittance with s-polarized incident light as a function of
the incident angle. (a) Schematic diagram of s-polarized light incident on a
hole array and (b) transmittance of a square hole array (A14-1)


6''' ~ '


--- 0
-- 2
-- 4
-- 6
80
8
--100
120
--140
---16
---180
- 200


I I I I *


00


00











00


1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

no-


k

J-7


A


2200 2400 2600 2800 3000 3200 3400
Wavelength(nm)
(b)

Figure 5-8. Measurement of transmittance with p-polarized incident light as a function of
the incident angle. (a) Schematic diagram of p-polarized light incident on a
hole array and (b) transmittance of a square hole array (A14-1)

The dip at 2860 nm also shows the same spectral behavior when the incident angle

increases, splitting into two dips, one of which shifts to shorter wavelengths and the other

dip shifts to longer wavelengths with increasing incident angle.


--02
-204
- 60

80
--6
8



140
- 160
- 180









We cannot easily distinguish how the second highest peak at 2450 nm changes. It

is a very interesting feature that the transmittance of the s- and p-polarizations behave

very differently as a function of the angle of incidence.

Dependence on Hole Shape

In this section, we discuss dependence of the transmittance on the hole shape and

the in-plane azimuthal angle of polarization. For this measurement, we prepared four hole

array samples which have different shapes and sizes of holes. Those arrays are shown in

Figure 4-1. The four samples are: 1) an array of square holes with 1000 nm x 1000 nm

hole size and 2000 nm period (A18-1), 2) an array of rectangular holes with 1000 nm x

1500 nm hole size and 2000 nm period (A18-2), 3) an array of slits with 1000 nm width

and 2000 nm period (A18-3) and 4) an array of square holes on rectangular grid with

1000 nm x 1000 nm hole size and 1500 nm period for x-axis direction and 2000 nm

period fory-axis direction (A18-4).

Square Hole Arrays

Figure 5-9 shows the transmittance of the square hole array as a function of

polarization angle. The spectra at all polarization angles (0 45 90 ) are the same.

The transmittance maximum occurs at 2940 nm with an intensity of 60% for all three

polarization angles. The behaviors at 0 0 and 90 0 polarization angles are due to

geometrical symmetry of the square hole array. For 45 polarization angle, the electric

field has decomposed into 0 0 and 90 0 components, making the spectra at 0 0 and 90

polarization angles to be the same.

The transmittance peak at 2940 nm shows Fano line-shape which we discussed in

Chapter 2. This Fano line-shape is a typical feature of the enhanced transmission of sub-






59


wavelength hole arrays even though it is still not clear if it is due to the superposition of

contributions from the resonant and non-resonant scattering processes in transmission

mechanism.


1000 2000 3000 4000
Wavelength(i(m)


Figure 5-9. Transmittance of square hole array (A18-1) as a function of polarization angle.
The inset shows a SEM image of the square hole array.

Rectangular Hole Array

The transmittance of the rectangular hole array for polarization angles of 0 and 90

0 are shown in Figure 5-10. As shown in the figure, it is evident that the transmission of

the 0 0 polarization angle is very different from that of the 90 0 polarization angle.

For the 90 0 polarization angle, the transmittance maximum has an intensity of

83 % at 3300 nm. This peak disappears for 0 0 polarization angle while another peak

appears at 2900 nm which shows an intensity of 43 %. This difference between the









transmittance of 0 0 and 90 0 polarization angles shows that the position of maximum

transmittance strongly depends on polarization angle due to the asymmetry of rectangular

holes.


0 1000 2000 3000 4000
Wavelength(pm)


Figure 5-10. Transmittance of a rectangular hole array (A18-2) for in-plane polarization
angles of 0 0 and 90 The inset shows a SEM image of the rectangular hole
array.

Another interesting difference between the transmittance of 0 0 and 90

polarization angles is the line-width of the maximum peak. Figure 5-10 shows that the

line-width of the maximum peak in the transmittance of the 90 0 polarization angle is

much broader that that of the 0 0 polarization angle.

There is the second highest peak around 2300 nm in the transmittance spectra of 0 0

and 90 0 polarization angles. These peaks are located at the same position with a similar










line-width. This is a different spectral behavior compared to the large peaks at 2900 nm

and 3300 nm.


1.0 I i I i

0.9 900
Slit array 90
0-8 -00 00
07 90 0
007

a 0.6 [

._ 0.5
(U
= 0.4
I-
0.3

0.2

0.1

0 0
0 1000 2000 3000 4000
Wavelength(jpm)


Figure 5-11. Transmittance of a slit array (A18-3) for in-plane polarization angles of 0 o
and 90 0. The inset shows a SEM image of the slit array.

Slit Arrays

The transmittances of the slit array for 0 0 and 90 0 polarization angles are shown in

Figure 5-11, along with a SEM picture of the array (inset). The 0 0 polarization direction

is parallel to the slit direction and the 90 0 polarization is perpendicular to the slit

direction. The transmittance at 90 0 polarization angle shows a very broad transmittance

peak around 4000 nm with an intensity of 73 %. This peak disappears for 0 0 polarization

angle. This transmittance behavior of slit array is expected as slit arrays are used as a

wire grid polarizer [52].









The transmittance of the slit array also shows a second maximum peak for both 0

and 90 polarizations around 2300 nm which is the same position as the square and the

rectangular hole arrays. But, in the transmittance of the 0 polarization angle, we hardly

recognize the dips which exist in the transmittance of the 90 polarization angle at 2000

nm and 2800 nm. This is probably due to an absence of periodic grating structure in the

direction of 0 0 polarization angle.


1000 2000 3000 4000
Wavelength(nm)


Figure 5-12. Transmittance of a square hole array on a rectangular grid (A18-4) for
polarization angles of 0 45 and 90 The inset shows a SEM image of the
square hole array in a rectangular grid.

Transmission of Square Hole Array on Rectangular Grid

In order to see the effect of different periods in two orthogonal polarization angles,

we prepared a square hole array on a rectangular grid (A18-4). As mentioned previously,

the periods in the 0 0 and 90 0 polarization angles are 1500 [m and 2000 [m, respectively.









The hole size is 1000 nm x 1000 nm which is the same as that of the square hole array

(A18-1).

Figure 5-12 shows the transmittance of the square hole array on a rectangular grid

for 0 o, 45 o and 90 o polarization angles. The transmittance at the 90 0 polarization shows

a sharp maximum peak at 3020 nm and a second maximum at 2270 nm. The peak at 3020

nm disappears for the transmittance of the 0 0 polarization angle. But the peak at 2270 nm

remains at the same position with a little higher intensity for the 0 0 polarization angle.

There is a small peak at 3000 nm in the spectrum of the 0 0 polarization angle and this

might be due to a misalignment of polarization at the angle of 0 .

Refractive Index Symmetry of Dielectric Materials Interfaced with Hole Array

Most of the samples that we have prepared are asymmetric structures with a fused

silica substrate (or ZnSe substrate)/a periodic array on sliver film/air, as shown in Figure

5-13 (a). But there were some reports proposed an increase of the transmittance when

sample has refractive index symmetry of dielectric materials on both sides of hole array

[58] In order to test an effect from this refractive index symmetry, we used photo resist

(Microposit S1800, Shipley) and PMMA (NanoPMMA, MicroChem) as a dielectric

material to make the refractive index symmetry with fused silica substrate. The refractive

indices of PR and PMMA are approximately 1.6 and 1.5, respectively [59, 60], and the

refractive index of fused silica is about 1.4 [42].

First, we measured transmittance of an original sample which is the square hole

array (A14-1). Then, we coated PR or PMMA with a thickness of 150 nm on the top of

hole array and measured the transmittance. Figure 5-13 shows schematic diagrams of

each step of the sample preparation for measurement.









Figure 5-14 and Figure 5-15 show the transmittance of square hole arrays on fused

silica substrate and ZnSe substrate, and the same hole arrays with PR coated on the top.

When the PR (n 1.6) is coated on the hole arrays, the transmittance maximum of the

hole array on fused silica substrate shifts more than 600 nm to longer wavelengths while

the peak of the hole array on ZnSe substrate shifts only 60 nm which is small compared

to that of the hole array on fused silica substrate. There is a small increase in the peak

intensity for the hole array on ZnSe substrate but there is almost no increase for the hole

array on fused silica substrate. The dip at 2800 nm also shifts about 100 nm to longer

wavelengths in the hole array on fused silica substrate but the same dip of ZnSe substrate

sample shifts to longer wavelengths slightly.

In addition, we used PMMA (n z 1.5) for this index symmetry experiment. As we

know, the refractive index of PMMA is almost same as the refractive index of fused silica.

Figure 5-16 shows transmission spectra of the square hole array (A14-1) with and

without PMMA on top of the hole array. The transmittance of PMMA coated hole array

shows the maximum transmittance at 3210 nm. This peak is shifted about 200 nm to

longer wavelengths from 3010 nm where the maximum transmittance of the hole array

without PMMA coating occurs. Another transmittance in Figure 5-16 is measured with

the same hole array but with another fused silica substrate attached on the top of PMMA.

The transmittance with the second fused silica substrate shows no shift in the positions of

peak and dip but a small decrease in transmittance intensity compared to the spectrum of

the PMMA coated hole array. The transmittance decrease is probably due to reflection

and absorption by the additional fused silica substrate attached on the top of PMMA.










Ag pattern (100 nm)


(a)
Fused silica (1mm)

Photo resist or PMMA (150nm)


Fused silica


Fused silica


Fused silica


Figure 5-13. Schematic diagram of sample preparation (a) an original square hole array
(b) a PR (or PMMA) coated square hole array (c) another fused silica
substrate attached on top of PR (or PMMA)


1.0



0.8



O
) 0.6
C-,


E
u,
c 0-4
I-


0-2



0.0


1000 2000 3000 4000
Wavelength(nm)


5000


Figure 5-14. Transmittance of a square hole array (A14-1)
and without PR coated on the top


on fused silica substrate with











1.0 -i


Square hole array on Ag/ZnSe
0.8 -- uncoated
-- PR coated


S0.6


E
o
c 0.4



0.2



0.0
0 2000 4000 6000 8000 10000
Wavelength(nm)


Figure 5-15. Transmittance of a square hole array (A14-1) on ZnSe substrate with and
without PR coated on the top of hole array


00 1
2200


2400 2600 2800 3000 3200
Wavelength(nm)


Figure 5-16. Transmittance of a square hole array (A14-1) on fused silica substrate with
and without PMMA coated on the top of hole array with the second fused
silica substrate attached on the top of PMMA.


Square hole array on Ag/fused silica glass (quartz)
uartz / Ag film / Air
Quartz I Ag film / PMMA
-Quartz / Ag film / PMMA / Quartz






67


Even though we expected a remarkable increase of the transmittance in the case of

the fused silica substrate samples, it is hard to observe an increase in the measured

transmittance. But this result shows that the peak and the dip of the hole array on fused

silica substrate shift a lot more than the hole array on ZnSe substrate. It means that the

spectral shifts of peak and dip by an addition of the index symmetry layer depend on the

substrate material of the hole array.














CHAPTER 6
ANALYSIS AND DISCUSSION

In Chapter 5, we have shown the transmittance of various structures of hole arrays,

which have different geometrical parameters (period, film thickness, incident angle and

hole size) and the refractive indices of dielectric material. In this chapter, we will analyze

and discuss a few important features. First, we compute the theoretical predictions for the

positions of peaks and dips, and compare them with experimental data. Second, we

discuss the transmittance dependence on incident angle for s- and p-polarized light. Third,

we discuss the dependence on hole shape and size.

Prediction of Positions of Transmission Peaks

We need to recall one of surface plasmon equations which predicts the position of

resonant transmittance peaks in two dimensional hole array.

a = isin0, +(i2+j2) dm -j2 sin2 20
l i2 +j2 d + Em


for non-normal incidence (Oo # 0) (2-42)

a
A+ao dm 2 for normal incidence (Oo = 0) (6-1)


With this equation, we can calculate wavelengths of the surface plamon resonant

transmission peaks of a two dimensional hole array. For this calculation, we need the

dielectric constants of air, substrate materials and metal which is silver in this work. First,

we know that the dielectric constant of air is 1. The substrate we mostly used is fused

silica glass substrate. The dielectric constant of fused silica glass is 2.0 for a wavelength









range between 2000 nm and 3000 nm. We also need to calculate the dielectric constant of

silver. Generally, the dielectric constant of a metal is a strong function of frequency (or

wavelength) and has a complex form:

,m = ,mr + im, (6-2)

where ,mr and m are real and imaginary parts of es. em, is mainly associated with

absorption of metal. em in Eqs. (2-42) and (6-1) is usually considered as the real part of

dielectric constant of metal, Emr.

For calculation of em in Eq. (6-1), we consider silver as an ideal metal and use the

Drude model for free electrons. Eq. (2-35) gives the dielectric function of a Drude metal:



0) V
,1 = 1-- 1 (2-35)


where Ap is the bulk plasma wavelength of the metal (cop is the bulk plasma frequency).

We use 324 nm for the bulk plasma wavelength, as measured in this experiment.

From calculation of the dielectric constant of silver, we found that EAg for = 3000

nm is about -84.75 (and eAg = -49.71 for X = 2000 nm). With these numbers, we get the

wavelengths of the resonant transmittance peaks for hole arrays with a period of 2 [tm

using Eq. (6-1). The result of calculation is shown in Table 6-1.

Table 6-1. Calculated positions of surface plasmon resonant transmittance peaks for three
interfaces of 2000 nm period hole arrays at normal incidence (Ed of air, fused
silica and ZnSe are 1.0, 2.0 and 6.0, respectively)

/ fused silica / metal ZnSe / metal
( i, j ) air / metal interface interface interface
interface interface
(0, 1l) and (l, 0) 2020 nm (P2) 2860 nm (P1) 5080 nm (P4)

(+1, +1) 1450 nm (P3) 2040 nm (P2) 3590 nm (P5)










Comparison of Calculated and Measured Positions of Transmittance Peaks and
Dips

Figure 6-1 indicates the calculated positions of the transmittance peaks in the

measured transmittance of a square hole array made on a fused silica substrate (A18-1).

As shown in this figure, the calculated positions of the peaks do not match accurately

with the peak positions in the measured transmittance. The difference between P1 and the

maximum peak position in the measured transmittance is about 80 nm. The spectral

difference for the second highest peaks is 140 nm. Even though many people still believe

in the role of surface plasmon in the enhanced transmission of sub-wavelength hole

arrays, the discrepancy between the peak positions calculated with Eq. (6-1) and the

measured peak positions still remains as an unsolved problem.


1.0 I I I I



0.8

P1
S0.6 P2
a P3

E
c 0.4
I--

0.2



0.0
0 1000 2000 3000 4000
Wavelength(nm)


Figure 6-1. Comparison of calculated peak positions with measured transmittance data.
Transmittance measured with a square hole array (A18-1) is shown. P1, P2
and P3 are the calculated positions of three transmittance peaks.









Actually, the surface plasmon equation, Eq. (2-42) (or, Eq. (6-1) for normal

incidence), has some approximations that are not applicable to real systems. First, the

dispersion relation of surface plasmon which is used to derive Eq. (2-42) is not for a

system of periodic hole array structure but for a plane interface of metal and dielectric

those are infinitely thick. This will give a difference in the dielectric constant of the

system. Second, the surface plasmon equation is based on the long wavelength

approximation. Thus, it does not depend on the shapes and the sizes of holes, but it

depends only on the periods of hole arrays. Third, as we mentioned in Chapter 2, the

surface plasmon equation is derived for a system with an infinitely thick metal which is

not possible in a real system. As the metal film is infinitely thick, it does not consider the

effect from an interaction between two interfaces. But, in a real system, the thickness of

metal film is finite, so there must be the interaction between two interfaces. Furthermore,

if there are holes in the metal film, the interaction will be stronger. These approximations

could be a reason for the difference between the calculated and the measured peak

positions.

Another interesting feature is the dips in the transmittance. It is known that the

transmittance minima of sub-wavelength hole arrays are due to Wood's anomaly.

According to Wood's anomaly, the minima (dips) appear at wavelengths where the

incident light is diffracted into the surface direction by periodic grating structures, and the

transmittance becomes a minimum. Eq. (6-2) is the diffraction equation of one

dimensional grating for normal incidence [52].


An = d sin 0 (6-3)
n









where d is the groove spacing, n is an integer, Ed is the dielectric constant of the dielectric

material and 0is the diffraction angle. As Wood's anomaly happens at the diffraction

angle 0= 90 so there is no transmitted light at the wavelength:


Al =d (6-4)
n

If we consider two dimensional grating structure such as a hole array, n in Eq. (6-4)

is replaced by ,j2 + j2 and the equation becomes


A= ra (6-5)


where i andj are integers and a is the period of two dimensional hole array. Eq. (6-5) is

very similar with the surface plasmon equation, Eq. (6-1), except for the dielectric

constant. Because the dielectric constant of the metal is much bigger than that of

dielectric material, the peak positions predicted by Eq. (6-1) is very close to the dip

positions predicted by Eq. (6-5).

Table 6-2. Calculated positions of transmittance dips for three interfaces of 2 [tm period
hole arrays at normal incidence (Ed of air, fused silica and ZnSe are 1.0, 2.0
and 6.0, respectively)

fused silica / metal ZnSe / metal
( i, j ) air / metal interface interface interface
interface interface
(0, 1l) and (l, 0) 2000 nm (D2) 2800 nm (D1) 4900 nm (D4)

(+1, +1) 1430 nm (D3) 2000 nm (D2) 3460 nm (D5)

Table 6-2 shows the calculated positions of dips. Figure 6-2 shows the same

transmittance shown in Figure 6-1 with the positions of the dips indicated. As we can see

in Figure 6-2, the calculated positions of the dips coincide well with the positions of the

dips in the measured transmittance. This is different from the discrepancy of the peak









positions. The reasons why the positions of transmittance minima are matched better than

the transmittance maxima are: 1) the diffraction grating equation is derived for a periodic

structure, not for a plane surface as the surface plasmon equation, 2) the diffraction

grating equation is not dependent on the refractive index of the grating material (metal),

but only depends on the refractive index of the dielectric material. Figure 6-3 shows the

positions of the peaks and the dips for the ZnSe-metal interface with the measured

transmittance of a square hole array (A14-1) made on a ZnSe substrate. This comparison

between the calculation and the measurement for a hole array on a ZnSe substrate also

shows a discrepancy in the peak positions and a good coincidence in the dip positions.

1.0 I



0.8

P1
S0.6 P2
a P3

E D1
S0.4 D3 D2
t--

0.2



0.0
0 1000 2000 3000 4000
Wavelength(nm)

Figure 6-2. Comparison of the calculated transmittance peaks and dips with the
transmittance measured with a square hole array (A18-1) made on a fused
silica substrate. P1, P2 and P3 are the calculated positions of the first three
peaks and D1, D2 and D3 are the calculated positions of the first three dips.










1 -0 *--------- -- i -- ---------
1.0



0.8
P4
P5
S0.6 P2
c P3
D4
E D5
o, D3 D2
C 0.4



0.2
I- '






0.0
0 2000 4000 6000 8000
Wavelength(n rm)


Figure 6-3. Comparison of the calculated transmittance peaks and dips with the
transmittance measured with a square hole array (A14-1) made on a ZnSe
substrate. P4 and P5 are the calculated peak positions and D4 and D5 are the
calculated dip positions for the ZnSe-metal interface. P2, P3, D2 and D3 are
the positions of the peaks and the dips for the air-metal interface.

Dependence of the Angle of Incidence on Transmission

Fig. 6-4 shows the transmittance of an array of square holes (A14-1) on a silver

film. This transmittance was measured using unpolarized light at normal incidence. As

discussed before, the peak A and the dip B are attributed to (i, j) = (+1, 0) or (0, 1)

modes on the fused silica-metal interface, and they don't vary with changing the

polarization direction of the incident light at normal incidence.

In the previous chapter, we have seen that the transmittance varies with the angle of

incidence and also strongly depends on the polarization of the incident light.










In order to explain the spectral behavior of transmittance maximum on the angle of

incidence, we need to recall the surface plasmon equation, Eq. (2-42). Even though the

surface plasmon equation has some drawbacks in its approximation, it is still useful to

explain the spectral behavior on the angle of incidence qualitatively. The surface plasmon

equation for oblique incidence was already introduced in Eq. (2-42) of Chapter 2, and

here we derive Eq. (2-42) using Eqs. (2-24) and (2-41):


k = -d-" Dispersion relation of surface plasmon (2-18)
C ed +


k = k +ky +ig +jg,


1.0-

0.9

08 -

0.7

0.6

0.5

0.4

03

0.2

0.1

0.0
2200


g, = g = 2a,
a,


2400 2600 2800 3000
Wavelength(nm)


3200 3400


Figure 6-4. Transmittance of a square hole array (A14-1) measured using unpolarized
light at normal incidence.


(2-34)


\/B (+1,0)Q, (0,+1)Q
| I I













Plane of incidence


Photon o0


Figure 6-5. Schematic diagram of an excitation of surface plasmon by the incident light
on two dimensional metallic grating surface. An azimuthal angle of the
incident light is 0 so that the wave vector of the incident light is always on
the plane of incidence and on the x-axis.

As we did in Chapter 2, we set the in-plane azimuthal angle to be 0 so that the

incident light is on the x-z plane which is the plane of incidence. This is shown in Figure

6-4. The magnitude of k in oblique incidence with 0o is ko sin0o and k = 0 Therefore,

the magnitude of ks is


,2 2 1n 1/2+
aI ) a,


(6-6)


From Eq. (6-6) and Eq. (2-24), we get an equation as


c red m


k, sin8, +i- + ]-
S2) (


(6-7)


ksp














Phot


0,2

0.1

0,0
2200


:on


Wavelenglh(nmr

(b)


Figure 6-6. Transmittance with s-polarized incident light. (a) Schematic diagram of (0, 1)
and (0, -1) modes excited on a square hole array for s-polarization and (b)
transmittance of a square hole array (A14-1) as a function of incident angle
for s-polarization. The peak A and the dip B are attributed to (0, 1) and (0, -1)
modes on the fused silica-metal interface that are degenerated in the s-
polarization case.


I i I I
--0
---2



14
--6---- -
8 A





120 /
--- 20 f ..... .



: -"i l... B(O, 1)Q


mX




V








































4-(1, 0)Q
(-1. O)Q
/ N-


t'-
---18,-
-- 20' ^-- *""*



"-, ., < ---^-"


-.


1, o0)QB(:1, 0)q
i00 2800 300C
Wavelenglh(nmr


N


(b)

Figure 6-7. Transmittance with s-polarized incident light. (a) Schematic diagram of(1, 0)
and (-1, 0) modes excited on a square hole array for p-polarization and (b)
transmittance of a square hole array (A14-1) as a function of the incident
angle for s-polarization. The peak A and the dip B are attributed to (1, 0) and
(-1, 0) modes on the fused silica-metal interface that are separated with
changing the angle of incidence in the p-polarization case.


0.2

0.1

0.0
2200


______











3200

3000

2800


I


F


I-- I --mm-Im m--m-m-,-_
Smaximum peak

-m--m---mm---m-,--mmmm

(0,1)S and (0,-1)S-



2nd highest peak



-- m -(0,1)A and (0,-1)A
Sm-m"----m--" m __m.
--I~--
- ---- measurement
-. --- calculation
I I I + I


0 4 8 12 16 20
Incident angle (0)

(a)


3000 -


Incident angle ()

(b)


Figure 6-8. Peak and dip position vs. incident angle for s-polarization. (a) Peak position
and (b) dip position. The red and the blue squares indicate the measured and
the calculated positions, respectively.


E 2600
C

c
2400

0C
. 2200

2000
2000


1800

1600


3200


2800

2600

2400

2200

2000

1800

1600

1400


---1=-- -m--m m
L[m *-U ---,
(0,1)S and (0,-1)S










---- measurement
calculation











3600

3400

3200

S3000

0 2800
Co
- 2600
CD

2400

2200

2000


3600

3400

3200

S3000

o 2800
0
C- 2600

2400

2200

2000


4 8 12 16 20

Incident angle ( )

(a)


4 8 12 16 20

Incident angle ()

(b)


Figure 6-9. Peak and dip position vs. incident angle for p-polarization. (a) Peak position
vs. incident angle and (b) dip positions vs. incident angle for p-polarization.
The red and the blue squares indicate the measured and the calculated
positions, respectively.










With some steps of calculation and k, -, where A is the wavelength of the
c cA

incident light, we get Eq. (2-42) for the position of resonant peak at oblique incidence:


= = a -isin8 + (i2 +j2) EdEm j2 sin 20 (2-42)
p i +j2 e+ JM


For s-polarization case, the electric field of incident light is parallel to the rotating

axis which is y-axis, so that only (0,j) modes are excited. This means that the modes

responsible for the transmittance maximum in the s-polarization case are (0, 1) and (0, -1)

mode on the fused silica-metal interface. This is shown in Figure 6-6.

From Eq. (2-42) we notice that there are onlyj2terms, which means that the (0, 1)

and (0, -1) modes on fused silica-metal interface are degenerate inj2. This is the reason

why there is no splitting in the peak A with changing the angle of incidence in the s-

polarization case.

On the other hand, for the p-polarization case, the electric field of the incident light

has two components which are parallel to the x-axis and the z-axis, but there is noy-axis

component. The x-axis component of electric field allows only (i, 0) modes to be excited

on the metal surface. Therefore, the peak A in the p-polarization case is attributed to (1, 0)

and (-1, 0) modes on the fused silica-metal interface. These modes are governed by a

linear term ofi in the Eq. (2-42) which is i sin 0. By this term, the (1, 0) and (-1, 0)

modes are separated with changing the angle of incidence, which shows a splitting of the

peak A in the transmittance.

In addition, in Figure 6-6 (b) and Figure 6-7 (b), there is the dip B at 2860 gm for

normal incidence. The dip B shows the same spectral behavior as the peak A. As

discussed before, this dip has been known as the Wood's anomaly. Eq. (6-5) is an









equation for the positions of the transmittance dips for normal incidence. If we consider

oblique incidence, the momentum conservation equation is the same with Eq. (2-34). But

the dispersion equation is different from the case of the transmittance peaks. The

dispersion equation for the diffracted (grazing) light is


k=-9 (6-8)
c

Combining with Eq. (2-34) and a few steps of calculation give the positions of

transmission dips:

Adp = a2 {-isinOo + (2+2)d 2 sin2 0 (6-9)


As we see from this equation, the position of the transmittance dip is also

dependent on the angle of incidence, which is same as the transmittance peak. This is the

reason why the dip B also shows the same spectral behavior as the peak A.

Figures (6-8) and (6-9) show the positions of the transmittance peaks and the dips

as a function of the incident angle for the s-polarization and the p-polarization,

respectively. As discussed above, we can see a spatial gap (a discrepancy) between the

calculated peak positions and the measured peak positions. For both polarizations, the

gap of the maximum transmittance peaks is about 200 nm and that of the second highest

peaks is about 400 600 nm. But the positions of the dips between the calculation and

the measurement are well matched. For the p-polarization, Figure 6-9 shows the splitting

of the peak and the dip when the incident angle increases.


Drawbacks of Surface Plasmon and CDEW

Another interesting feature that we observe is that there exists a resonant

transmission in the case of s-polarization. As shown in Chapter 2, the surface plasmon









does not exist for s-polarized incident light. This means that the surface plamon cannot be

the reason for resonant transmission with s-polarization. Moreno et al. [61] reported in

their paper that a resonant transmission is also possible for s-polarization. They proposed

that the resonant transmission is not due to the surface plasmon, but due to a coupling of

the incident light to surface mode. As we noticed, there is no difference between s-

polarization and p-polarization for normal incidence due to the geometrical symmetry.

Therefore, we cannot say that the surface plasmon is only responsible for the resonant

transmission of p-polarization case, while something else is responsible for the

transmission of s-polarization. Therefore, at least, we can say that the resonant

transmission on both s- and p-polarizations is not mainly due to the surface plasmon.

In addition to this inappropriateness of the surface plasmon for the explanation of

the enhanced transmission with s-polarization, in their paper [9], Lezec at al. claimed that

the surface plasmon is not responsible for the enhanced transmission of sub-wavelength

hole arrays because of the following reasons: 1) the difference of the peak positions

between the surface plasmon model and experimental data (we already discussed about

this previously), 2) an observation of the enhanced transmission of the hole arrays in Cr

for NIR region and tungsten for VIS region which do not support the surface plasmon, 3)

the demonstration of the enhanced transmission with numerical simulation for hole arrayz

in a perfect metal that also do not support the surface plasmon.

In contrast, the CDEW cannot explain some parts of experimental features. First,

the CDEW model cannot explain the spectral variations of s-polarization and p-

polarization as a function of the incident angle because the CDEW is based on the scalar

diffraction theory [50], so it does not depend on polarization directions. Second, J.









Gomez Rivas et al. [24] proposed in their paper about the enhanced transmission in

terahertz (THz) region that the enhanced transmission of sub-wavelength hole array in a

doped silicon film depends on temperature, because the mobility of the charge carriers in

the doped silicon film depends on temperature. This means that the enhanced

transmission of hole arrays on the doped silicon is attributed to the charge carriers as the

electrons in a metal film. This could be an evidence of that the surface plasmon is

responsible for the enhanced transmission in the metal.

Dependence of Hole Shape, Size and Polarization Angle on Transmission

In the previous chapter, we showed the transmittance of the different hole array

structures. We have seen that the transmittance of each hole array varied with the in-

plane polarization angle except for the square hole array due to its symmetry in x andy

directions. Now we compare three different hole arrays, square hole array, rectangular

hole array and slit array, with the same polarization angle. Figure 6-10 and Figure 6-11

show transmittance of the three hole arrays with polarization angles of 0 0 and 90 ,

respectively. As each hole array has an open fraction which is different from those of

other hole arrays, we rescaled the x-axis with transmittance divided by open fraction to

compare more directly the data for the different hole array. The open fractions for the

square hole array, rectangular hole array and slit array are 18 %, 29 % and 50 %,

respectively.

For the polarization angle of 0 Figure 6-10 (a) shows schematic diagrams

comparing three different arrays with the polarization angle of 0 0 and the lower panel

shows the transmittance of those arrays with the same polarization angle. The

transmittance of the square hole array (A18-1) shows the maximum peak intensity of 3.3









at 2940 nm. But, the intensity of the maximum peak of the rectangular hole array

decreases to 1.5. Finally, this maximum peak disappears for the slit array. The position of

the maximum peak shifts to shorter wavelengths slightly with increasing length of hole

edge parallel to polarization direction. Thus, the intensity of maximum peak is strongly

dependent on the length of hole edge parallel to polarization direction, whereas the

position of the maximum peak is not affected by changing the length of hole edge parallel

to polarization direction. For the peak positions, there is not enough space in shorter

wavelengths for the peak to be shifted because the shift to shorter wavelengths is stopped

by the dip at 2800 nm.

In addition, we can see a change in the dips at 2800 nm and 2000 nm. The dips in

the transmittance of the square hole array are well established. But, those dips rise up in

the transmittance of the rectangular hole array. These dips finally disappear for the slit

array. As we mentioned in the previous chapter, we understand this disappearance of the

dips for the slit array because there is no grating structure in the 0 0 polarization angle in

the slit array. But, for the rectangular hole array, even though the rectangular hole array

has a grating structure with a period of 2 tm, which is the same as the period of square

hole array, in the 0 0 polarization angle, the transmittance minimum is less well defined.

The increase in the transmittance at the minima is not due to the increase of the open

fraction because we already rescaled the y-axis with transmittance divided by open

fraction. Thus, the effect of larger open fraction is eliminated. The only parameter that we

consider here is the length of hole edge parallel to the polarization angle of 00, which is

different in each array. This indicates that the spectral feature of dips in transmittance

measured with a certain polarization direction is not only dependent on the period of hole









array in the direction parallel to polarization, but also on the length of hole edge parallel

to the polarization direction.

Another interesting feature in these transmittance is the intensity of the second

highest peak. Different from the maximum peak spectra, the second highest peak in each

spectrum shows the intensity which is the same as the open fraction of each array.

Figure 6-11 shows schematic diagrams comparing the three different arrays with

the polarization angle of 90 and the lower panel shows the transmittance of the three

hole arrays with the same polarization angle. Same as the 0 polarization angle, the

transmittance of the square hole array with the polarization angle of 90 shows the

maximum peak at 2940 nm. In the transmittance of the rectangular hole array, the

maximum peak shifts to longer wavelengths and shows a lower intensity with a broader

line-width. The transmission spectrum of slit array shows that the peak shifts even more

to longer wavelengths and has the lowest intensity with the broadest line-width. The y-

axis of these spectra is also rescaled with transmittance divided by open fraction, so the

effect of open fraction in the transmittance is eliminated.

As we mentioned before, we observed the red shift of the maximum peak with

increasing the dimension of hole edge which is perpendicular to polarization direction.

The maximum peaks of the rectangular hole array and the slit array occur at 3300 nm and

4000 nm, which are shifted 350 nm and 1050 nm from the maximum peak position of the

square hole array, respectively. This means that the position of the maximum peak is

strongly dependent on the length of hole edge perpendicular to the polarization direction.

In addition to the red shift of the maximum peak, the transmittance show a lesser

maximum peak intensity and a broader line-width with increasing the length of hole edge









perpendicular to the polarization direction. This observation tells us two different cases:

first, the resonant transmission becomes stronger with a shorter hole edge, which shows

the strong and sharp peak, second, the direct transmission from the front surface to the

back through the bigger holes becomes stronger with longer hole edge, which shows the

low and broad transmittance peak.

The second highest peak is also very interesting in the case of 90 0 polarization

angle. The second highest peak shows almost the same features (the peak position, the

intensity and the line-width) with increasing the length of hole edge perpendicular to the

polarization direction. This is very different from the spectral behavior of the maximum

peak. But, we are still not sure what gives this difference between the maximum peak and

the second highest peak.

The dips appear with a similar intensity at the fixed positions which are 2800 nm

and 2000 nm in all three transmission spectra except the dips of the slit array are a little

higher than others. This is absolutely due to the same periodic grating structures of the

three hole arrays in the polarization direction of 90 .

CDEW and Trapped Modes for Transmission Dependence on Hole Size

The CDEW model predicts the red-shift and the broader line-width for larger holes.

It explains those features with a reduction of the effective number of hole that contributes

to the resonant transmission. When the hole size becomes bigger, the bigger holes act as

leakage channels for the CDEW, so each hole is reached by CDEWs from fewer holes.

This effective reduction in the number of holes contributing to the resonant transmission

causes a weakness of resonant transmission, thus the transmittance shows the red-shift

and the broadening of the peak.