| Project/Area Number |
25246026
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Thin film/Surface and interfacial physical properties
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| Research Institution | Tokyo Gakugei University (2015)
The University of Tokyo |
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Principal Investigator |
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| Co-Investigator(Kenkyū-buntansha) |
AKIMOTO Koichi 日本女子大学, 理学部, 教授 (40262852)
SHIRASAWA Tetsuroh 産業技術総合研究所, 計量標準総合センター, 主任研究員 (80451889)
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| Project Period (FY) |
2013-04-01 – 2016-03-31
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| Project Status |
Completed (Fiscal Year 2015)
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| Budget Amount *help |
¥46,150,000 (Direct Cost: ¥35,500,000、Indirect Cost: ¥10,650,000)
Fiscal Year 2015: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
Fiscal Year 2014: ¥15,080,000 (Direct Cost: ¥11,600,000、Indirect Cost: ¥3,480,000)
Fiscal Year 2013: ¥27,560,000 (Direct Cost: ¥21,200,000、Indirect Cost: ¥6,360,000)
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| Keywords | 表面界面構造 / Ｘ線回折 / トポロジカル絶縁体 / 位相問題 / ホログラフィ / 反復位相回復 / 電子密度分布 / 原子分解 / 表面構造 |
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| Outline of Final Research Achievements |
Surface x-ray diffraction is a powerful method of studying the atomic-scale structure and morphologies of surfaces and interfaces. We have studied the structure of Cu-doped Bi2Se3 ultra-thin films and the Si(111)-5x2-Au surface. We could analyze the structures as electron density with atomic, or atomic-layer resolution, using highly developed analyzing methods such a holographic method and phase retrieval methods.
We showed Cu is intercalated into van der Waals gaps of Bi2Se3 quintuple layers, and determined the dependence of the gap distance on the concentration of Cu as well. Our resistivity measurements at low temperatures never showed superconductivity. This result, casting a question on a previous report indicating superconductivity, is getting a consensus.
We also determined the surface structure of Si(111)-5x2-Au, that has been in dispute for a long time of about a half-century.
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