| Project/Area Number |
17340095
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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 |
Condensed matter physics I
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| Research Institution | Osaka University |
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Principal Investigator |
AKAI Hisazumi Osaka University, Department of Physics, Graduated School of Science, Professor (70124873)
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| Co-Investigator(Kenkyū-buntansha) |
OGURA Masako Osaka University, Department of Physics, Graduated School ofScience, Assistant professor (30397640)
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| Project Period (FY) |
2005 – 2007
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| Project Status |
Completed (Fiscal Year 2007)
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| Budget Amount *help |
¥5,980,000 (Direct Cost: ¥5,500,000、Indirect Cost: ¥480,000)
Fiscal Year 2007: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
Fiscal Year 2006: ¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 2005: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | computational physics / computational materials design / diluted magnetic semiconductors / full potential KKR / spintronics / half-metals / hyperfine fileds / giant magneto resistance / 希薄磁性半導体 / 計算機ナノマテリアルデザイン / フルポテンシャルKKR / グリーン関数法 / 計算機マテリアルシミュレーション |
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| Research Abstract |
On the basis of first-principles electronic structure calculations, we have shown that various compounds semiconductors as well as TiO2, chalchopyrite-type compounds doped with more than two kind of magnetic ions such as Cr-Fe and V-Co may exhibit half-metallic antiferromagnetism. We further have calculated the magnetic transition temperature of them materials using the magnetic coupling constants, which are calculated by the Green's function method, combined with a cluster approximation. The results show that the magnetic transition temperature of some half-metallic antiferromagnetic semiconductors will exceeds the room temperature. We also have developed the computer code that enables us to calculate the DC conductivity of these materials using the Kubo-Greenwood formula. Specifically, we have studies the followings:
1) We have designed hetero-structures using II-VI compounds half metallic diluted antiferromagnetic semiconductors It was shown that the electron mattering dues to the existence of a possible anti-phase domain boundary might cause GMR effect.
2) We have proposed the method to verify the half-metallic antiferromagnetism. On a of the possibility is XMCD and the other is using NMR technique. We actually calculated K-edge XMCD absorption spectra and the hyperfine interactions of probe nuclei in half-metallic antiferromagnets.
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