論文 - 亀山 晃弘
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Crystallized hydroxyapatite coatings deposited by PLD with targets of different densities "jointly worked" 査読あり
M. Katto, K. Ishibashi, K. Kurosawa, A. Yokotani, A.Kameyama
8th International Conference on Laser Ablation 2005年9月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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Katto M., Kurosawa K., Kurosawa K., Yokotani A., Kubodera S., Kameyama A., Higashiguchi T., Nakayama T., Tsukamoto M.
Applied Surface Science 248 ( 1-4 ) 365 - 368 2005年7月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Applied Surface Science
We have deposited hydroxyapatite (HAp) films on Ti substrate by pulsed laser deposition using KrF excimer laser. We used HAp targets sintered at temperatures of 500, 700, 900 and 1100 °C with densities between 1.5 and 2.4 mg/mm3. SEM images of the coating surface revealed that the deposited films had spherical structures with diameter of 5 μm. X-ray diffractometry (XRD) analysis showed that the deposited films contained amorphous HAp. Films deposited with a target sintered at 900°C showed that poly-crystallized HAp coating was achieved at room temperature. © 2005 Elsevier B.V. All rights reserved.
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甲藤 正人, 黒澤 宏, 横谷 篤至, 窪寺 昌一, 亀山 晃弘, 東口 武史, 中山 斌義, 塚本 雅裕, 阿部 信行
電気学会研究会資料. OQD, 光・量子デバイス研究会 2004 ( 32 ) 7 - 11 2004年11月
記述言語：日本語 掲載種別：研究論文（研究会，シンポジウム資料等）
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ファイバグレーティングセンサ反射特性のシミュレーションによる解析
佐藤 明子, 福島 康広, 加藤 隆晴, 亀山 晃弘, 甲藤 正人, 横谷 篤至, 黒澤 宏
宮崎大學工學部紀要 33 111 - 116 2004年10月
記述言語：日本語 掲載種別：研究論文（大学，研究機関等紀要） 出版者・発行元：宮崎大学
Abstract ###Refractive indices of silica glass are well known to change when ultra violet light is irradiated. ###With the photo-refractive effect, regions with different refractive indices are generated in an optical ###fiber. Fiber Bragg Grating (FBG) that has a periodic structure of different refractive indices shows a ###sharp reflection spectrum at a wavelength. The center wavelength, width, depth and sub peaks of the ###reflection spectrum depend on the periodicity, index difference, and index distribution of the structure. ###However, it is considerably difficult to measure the indices of the structure, because the size is as ###small as an order of optical wavelength used. I simulate the reflection spectra by changing the length ###and intensity distribution within the laser beam and index change. By comparing the simulated ###spectra with there measured, I have found that the laser beam has Gaussian-type intensity distribution ###and that the spectra depend on the length and index change distribution. On the basis of the ###simulation, you can obtain the laser parameters for fabricating a desirable FGB.
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紫外レーザーを用いたファイバーグレーティングセンサーの作製と特性評価
加藤 隆晴, 佐藤 明子, 福島 康広, 亀山 晃弘, 甲藤 正人, 横谷 篤至, 黒澤 宏
宮崎大學工學部紀要 33 81 - 86 2004年10月
記述言語：日本語 掲載種別：研究論文（大学，研究機関等紀要） 出版者・発行元：宮崎大学
Abstract ###Recently in the field of architecture and civil, there is a great demand high performance sensor ###for Health Monitoring to guarantee the efficiency of buildings. Optical Fiber sensor development is ###now being watched with interest because it is not influenced magnetic field. Therefore it takes ###place of the strain sensors which using bridge connection until now. FBG that can apply as strain ###sensor was fabricated based on the UV photosensitivity of germanosilicate in the fiber core. The ###interference fringe was generated exposuring UV light through the phase mask with KrF Excimer ###Laser, this interference fringe made Brag Gratings in the Optical fiber core. FBG fabrication was ###performed changing rep-rate from 1OHZ to 600Hz,exposuring fluences from 5 to 20mmJ/cm(2乗). The ###specification value which demand as strain sensor is that the time of reach 1OdB refractivity is ###within 300 seconds, the spectrum wave shape of FWHM is within 1OOpm, the fraction strain after ###exposed UV light is 3.2%. In our observation we could attain that minimum of fabricating time is 6 ###seconds, exposuring length of a fiber line keeps above 8mm, which could minimize FWHM ###38pm,the maximum fracture strain afier exposed UV light is 5.79% to controlling exposuring ###fluences. High precision Optical Fiber Sensor was fabricated to optimize controlling expusuring ###fluences and multiplying rep-rate, we think.
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Kameyama A., Yokotani A., Kurosawa K.
Journal of Applied Physics 95 ( 8 ) 4000 - 4006 2004年4月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Applied Physics
The change in refractive index and second-order optical nonlinearity in silica glasses by a combination of x-ray irradiation and thermal poling are discussed. Two kinds of second-order optical nonlinearity, bulk nonlinearity spreading throughout the whole sample and near-surface nonlinearity localized in a thin layer near the sample surface are observed. A change in refractive index in the sample is also found. Both the bulk nonlinearity and the refractive index change, based on absorption spectra of the samples, are found to be associated with point defects.
DOI： 10.1063/1.1652239
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熱ポーリング石英ガラスにおける第2次非線形光学性に関する研究 査読あり
亀山晃弘
大阪大学大学院工学研究科博士論文 2003年12月
記述言語：日本語 掲載種別：学位論文（博士）
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Second harmonic generation in high-purity silica glasses by a combination of thermal poling and UV laser pulse irradiation "jointly worked" 査読あり
A.Kameyama, A. Yokotani, K.Kurosawa
The Third Asian Pacific Laser Symposium 2002(APLS2002) 3 86 - 89 2003年2月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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Kameyama A., Yokotani A., Kurosawa K.
Journal of the Optical Society of America B: Optical Physics 19 ( 10 ) 2376 - 2383 2002年10月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of the Optical Society of America B: Optical Physics
Ultraviolet laser pulses were found to introduce and destroy point defects that play a key role in the generation of second-order optical nonlinearities by thermal poling in high-purity silica glasses. The characteristics of the generation process depended largely on not only ≡Si-OH, O2, and H2 content of the glasses but also the sequence of thermal poling and the pulse irradiation. There were two different kinds of nonlinearity: one localized in a thin layer near the sample surface (near-surface) and a bulk one spreading throughout the sample. The near-surface and bulk nonlinearities are associated with ≡Si-O- and ≡Si≡Si≡, respectively. © 2002 Optical Society of America.
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亀山 晃弘, 田中 学, 横谷 篤至, 黒澤 宏
宮崎大學工學部紀要 31 117 - 123 2002年7月
記述言語：日本語 掲載種別：研究論文（大学，研究機関等紀要） 出版者・発行元：宮崎大学
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AgBiTe_2マトリックスにAg_2Te粒を分散させたことによる熱電特性の向上 : (AgBiTe_2)_<1-x>(Ag_2Te)_xの複合化効果 査読あり
榊原 務, 瀧川 靖雄, 亀山 晃弘, 黒澤 宏
日本セラミックス協会学術論文誌 110 ( 1280 ) 259 - 263 2002年4月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：公益社団法人日本セラミックス協会
We prepare composite materials that Ag_2Te grains were dispersed in AgBiTe_2 matrices with the compositions of (AgBiTe_2)_<1-x>(Ag_2Te)_x. The textures depend on the composition. We measured electrical conductivity, thermal conductivity, Seebeck coefficients and Hall coefficients as a function of the composition. Based on these data, we estimate Hall mobility and lattice thermal conductivity, and finally thermoelectric figure of merit. We show that the figure of merit is enhanced in the composite system by means of enhancement of phonon scattering at the grain boundaries.
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Second-order optical nonlinearity in high-purity silica glasses by thermal poling and UV laser pulses "jointly worked" 査読あり
A. Kameyama, A.Yokotani, K.Kurosawa
Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides,(BGPP’01, OSA) 198 - 200 2001年7月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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Kameyama A., Yokotani A., Kurosawa K.
Journal of Applied Physics 89 ( 9 ) 4707 - 4713 2001年5月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Applied Physics
A large second-order optical nonlinearity has been found to be generated in various kinds of silica glasses in which an even-order optical nonlinearity is inherently prohibited. Thermal poling is a typical procedure to generate such a second-order optical nonlinearity, but a mechanism behind the generation is not elucidated completely. It should be pointed out, however, that the nonlinearity was not added to high-purity silica glasses by poling. In this article, we show that the nonlinearity is generated in high-purity silica glasses irradiated by a KrF excimer laser before poling. We also show that the laser pulses erase the nonlinearity induced in the glasses. In addition to the laser irradiation effects on the generation and erasure, optical absorption and luminescence spectra in the glasses show that point defects of ≡Si-O- play a key role for the nonlinearity. © 2001 American Institute of Physics.
DOI： 10.1063/1.1360214
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石英ガラスを用いた波長変換デバイス「（共著）」
亀山晃弘、横谷篤至、黒澤宏
信学技報（電子情報通信学会レーザ量子エレクトロニクス） 7 - 11 2001年5月
記述言語：日本語 掲載種別：研究論文（その他学術会議資料等）
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エキシマレーザーを照射しながら熱ポーリングした石英ガラスの第２次非線形光学性「（共著）」
亀山晃弘、横谷篤至、黒澤宏
第41回ガラス及びフォトニクス材料討論会 41 25 - 26 2000年11月
記述言語：日本語 掲載種別：研究論文（その他学術会議資料等）
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亀山 晃弘, 横谷 篤至, 黒澤 宏
電気学会研究会資料. OQD, 光・量子デバイス研究会 2000 ( 47 ) 37 - 40 2000年10月
記述言語：日本語 掲載種別：研究論文（研究会，シンポジウム資料等）
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熱ポーリング石英ガラスにおける２次非線形光学性の発現「(共著)」
亀山晃弘、横谷篤至、黒澤宏
第40回ガラス及びフォトニクス材料討論会 69 - 70 1999年11月
記述言語：日本語 掲載種別：研究論文（研究会，シンポジウム資料等）
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Large second-order optical nonlinearity in thermally poled high-purity silica glass by a control of defects "jointly worked" 査読あり
A. Kameyama, A. Yokotani, K. Kurosawa
OSA Annual Meeting 1999 88 - 88 1999年10月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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Large second-order optical nonlinearity in thermally poled high-purity silica glass "jointly worked" 査読あり
A. Kameyama. A. Yokotani, K.Kurosawa
Conference on Laser and Electro-Optics (CLEO’99) 86 - 86 1999年5月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）
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Large second-order optical nonlinearity intheroally poled high-purity silica glass 査読あり
KAMEYAMA Akihiro
Summary of papers presented attche conference on lasers and electro-optics 165 1999年
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス）