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- Yasunori Furukawa
- National Institute for Research in Inorganic Materials, 1-1 Namiki, Tsukuba, 305-0044 Japan KAzuo NIwA
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- Shyunji Takekawa
- National Institute for Research in Inorganic Materials, 1-1 Namiki, Tsukuba, 305-0044 Japan
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- Kazuo Niwa
- NGK Spark Plug Co., Ltd., 2808 Iwasaki, Komaki, 485-8510 Japan
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- Hideki Hatano
- Corporate R & D Lab., Pioneer, 6-1-1 Fujimi, Tsurugashima, 350-2288 Japan
説明
<jats:p> High quality stoichiometric LiNbO<jats:sub>3</jats:sub> single crystals, 40 mm in diameter and 80-100 mm in length, have been successfully grown by the double crucible Czochralski method equipped with automatic powder supply system using radio-frequency heating and automatic diameter control system. Although some difficulties still exist in growing 3 inch size single crystals from offcongruent composition melts, our results demonstrate that stoichiometric LiNbO<jats:sub>3</jats:sub> crystals containing much less nonstoichiometric defects than congruent LiNbO<jats:sub>3</jats:sub> exhibit some advantageous properties for holographic data storage applications. This was confirmed by the results of two-beam coupling experiment and digital hologram test. In digital holographic data storage, we have demonstrated that stoichiometric LiNbO<jats:sub>3</jats:sub> shows more than 10 times larger photorefractive sensitivity than congruent LiNbO<jats:sub>3</jats:sub> In order to interpret the high performance of stoichiometric LiNbO<jats:sub>3</jats:sub>, we compared several relevant parameters such as electro-optic constants, photoconductivity, and photogalvanic constants between stoichiometric and congruent LiNbO<jats:sub>3</jats:sub> crystals. We report that material parameters are strongly dependent on the density of nonstoichiometric defects and control of these defects is of key importance in improving and tailoring those properties. </jats:p>
収録刊行物
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- Journal of Intelligent Material Systems and Structures
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Journal of Intelligent Material Systems and Structures 10 (6), 470-475, 1999-06
SAGE Publications