| Project/Area Number |
10450318
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
工業物理化学
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| Research Institution | THE UNIVERSITY OF TOKYO |
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Principal Investigator |
MIYAYAMA Masaru UNIVERSITY OFTOKYO, INSTITUTE OF INDUSTRIAL SCIENCE, ASSOCIATE PROFESSOR, 生産技術研究所, 助教授 (20134497)
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| Co-Investigator(Kenkyū-buntansha) |
NAKAMURA Yoshinobu UNIVERSITY OFTOKYO, SCHOOL OF ENGINEERING RESEARCH ASSOCIATE, 大学院・工学系研究科, 助手 (30198254)
KUDO Etsuichi UNIVERSITY OF TOKYO, INSTITUTE OF INDUSTRIAL SCIENCE, PROFESSOR, 生産技術研究所, 教授 (90205097)
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| Project Period (FY) |
1998 – 1999
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| Project Status |
Completed (Fiscal Year 1999)
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| Budget Amount *help |
¥11,100,000 (Direct Cost: ¥11,100,000)
Fiscal Year 1999: ¥4,000,000 (Direct Cost: ¥4,000,000)
Fiscal Year 1998: ¥7,100,000 (Direct Cost: ¥7,100,000)
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| Keywords | FERROELECTRICS / SINGLE ORYSTAL / BISMUTH LAYER-STRUCTURED OXIDES / INTERGROWTH STRUCTURE / REMANENT POLARIZATION / COERCIVE FIELD / FERROELECTRIC PHASE TRANFORMATION / 層状ペロブスカイト / 導電性ペロブスカイト / p型半導性 |
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| Research Abstract |
Bismuth layer-structured oxides (BLSOs) have the crystal structure composed of bismuth oxide layers and pseudo-perovskite layers, and known to show ferroelectric and piezoelectric properties with a strong anisotropy. In the present study, single crystals of several BLSOs were grown and correlations between crystal structure (the number of oxygen octahedron between bismuth layers : m) and ferroelectric properties were evaluated. It was found that the remanent polarization was larger in the BLSO with a high Curie temperature and the coercive electric field was smaller and the polarization reversal velocity was higher in BLSO with a large m. Polycrystals of several intergrowth structured BLSOs, in which perovskite layers with different m are stacked alternately in the lattice, were prepared and their ferroelectric phase transformations and ferroelectric properties were examined. The intergrowth BLSOs with m = 1-2 and 2-3 showed two phase transformations at temperatures of transformation of component materials, and that with m = 3-4 showed one transformation at the middle of transformation temperatures of component materials. Some of the intergrowth BLSOs with m = 2-3 and 3-4 was found to show a higher remanent polarization than those of component materials.
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