2016 Fiscal Year Final Research Report
Unusual magnetic order and Lifshitz transition in Ce-based Kondo semiconductors
| Project/Area Number |
26400363
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Multi-year Fund |
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| Section | 一般 |
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| Research Field |
Condensed matter physics II
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| Research Institution | Hiroshima University |
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Principal Investigator |
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| Co-Investigator(Renkei-kenkyūsha) |
UMEO Kazunori 広島大学, 自然科学研究支援開発センター, 准教授 (10223596)
KIMURA Shin-ichi 大阪大学, 大学院・生命機能研究科, 教授 (10252800)
YOKOYA Takayoshi 岡山大学, 大学院・自然科学研究科, 教授 (90311646)
EKINO Toshikazu 広島大学, 大学院・総合科学研究科, 教授 (40185103)
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| Research Collaborator |
ADROJA Devashibhai ラザフォード・アップルトン研究所, ISIS施設, 上級研究員
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| Project Period (FY) |
2014-04-01 – 2017-03-31
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| Keywords | 物性物理学 / 強相関電子系 / 近藤半導体 / セリウム化合物 / トンネル分光 / 光電子分光 / 磁気秩序 / リフシッツ転移 |
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| Outline of Final Research Achievements |
Strong hybridization of the 4f states with conduction bands in Ce-based Kondo semiconductors quenches the local magnetic moments and opens a gap in the hybridized band. However, newly found Kondo semiconductors CeT2Al10 (T=Ru, Os) order antiferromagnetically at unexpectedly high temperatures at 28 K. To elucidate this mechanism, we have made Os based samples by doping 4f holes, 5d holes, and 5d electrons, and studied the change in the electronic state by the bulk measurements as well as electron tunneling, optical conductivity, photoemission spectroscopy, and neutron scattering. The effects were found to strongly depend on the three different dopants. However, it is common that the magnetic order occurs after the density of states at the Fermi level decreases significantly on cooling. Thus, we propose that the Lifshitz transition involving the loss of a part of the Fermi surface induces the unusual magnetic order.
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| Free Research Field |
物性物理学
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