| Project/Area Number |
18H01162
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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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| Review Section |
Basic Section 13030:Magnetism, superconductivity and strongly correlated systems-related
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| Research Institution | The University of Tokyo |
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Principal Investigator |
Ogata Masao 東京大学, 大学院理学系研究科(理学部), 教授 (60185501)
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| Co-Investigator(Kenkyū-buntansha) |
苅宿 俊風 国立研究開発法人物質・材料研究機構, 国際ナノアーキテクトニクス研究拠点, 主任研究員 (60711281)
松浦 弘泰 東京大学, 大学院理学系研究科(理学部), 助教 (40596607)
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| Project Period (FY) |
2018-04-01 – 2021-03-31
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| Project Status |
Completed (Fiscal Year 2021)
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| Budget Amount *help |
¥17,290,000 (Direct Cost: ¥13,300,000、Indirect Cost: ¥3,990,000)
Fiscal Year 2020: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
Fiscal Year 2019: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000)
Fiscal Year 2018: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000)
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| Keywords | 多バンド効果 / 軌道磁性 / 輸送係数 / バンド間効果 / ノーダルライン |
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| Outline of Final Research Achievements |
Electrons in solids occupy the part of the infinite number of bands. Many electrical properties can be understood in terms of a single band near the Fermi energy. However, there are several physical quantities such as magnetic responses and transport properties, which can be understood in terms of the multi-band effects. Recently, the peculiar responses due to the multi-band effect have been clarified theoretically in Dirac electron systems and exitonic insulators. In this project, we clarified the following four points in a unified picture of the multi-band effect. (1) The multi-band effect in the conductivity under a magnetic field. (2) Derivation of the new formula for the orbital magnetic susceptibility using localized orbitals. (3) Physical properties in several nodal-line materials. (4) Exitonic insulators and photoinduced dynamics of Dirac electrons.
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| Academic Significance and Societal Importance of the Research Achievements |
多バンド効果という統一的な観点から、磁気応答や輸送現象、光誘起ダイナミクスについて種々の研究成果が得られた。とくに磁場下での輸送係数に対する多バンド効果の一般論や、局在軌道を用いた軌道帯磁率の新公式が得られたことは、今後の応用が期待できる。さらに、いくつかのノーダルライン物質の物性が明らかになったが、これらはノーダルライン物質の特定、新奇物性の開拓に役に立つと考えられる。また励起子絶縁体の熱応答特性、光誘起ダイナミクスによるトポロジカル相転移やディラック点のコントロールなども、さらなる研究の発展に役立つ。今後、系統的に新奇性能をもつ物質材料を創り出すときの指針に繋がると期待される。
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