2016 Fiscal Year Final Research Report
Quantum critical state and electronic structure of two-dimensional Kondo lattice
Project/Area Number |
26400337
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Condensed matter physics II
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Research Institution | Keio University |
Principal Investigator |
MATOBA Masanori 慶應義塾大学, 理工学部(矢上), 教授 (20229595)
|
Co-Investigator(Renkei-kenkyūsha) |
OKADA Satoshi 日本大学, 理工学部, 助教 (50453915)
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Project Period (FY) |
2014-04-01 – 2017-03-31
|
Keywords | 強磁性量子臨界状態 / 二次元近藤格子系 / 重い電子系 |
Outline of Final Research Achievements |
We have studied Cr-doping effects on the suppressed magnetism and the electronic structure of quasi-2D layered oxypnictide CeFePO with alternating stack of Ce2O2 and Fe2P2 layers to find two quantum critical points (Cr5%, Cr45%) and reveal novel Kondo lattice picture as follows. The increasing phenomena of the electronic specific heat of CeFePO indicates that the existence of the Kondo singlet was confirmed below 12 K (Kondo temperature). On the other hand, in Cr20%, the appearance of the ferromagnetic transition, the decrease with remarkable electronic thermal capacity and the Kondo breakdown phenomenon are observed below 6 K. Also, the increase of the magnetic phase transition temperature due to applied magnetic field is confirmed, indicating the existence of the ferromagnetic fluctuation in Cr20%. Moreover, from the 57Fe Mossbauer spectrum analysis of Cr50%, it is expected that Fe spin states change into a spin density wave (SDW) below 25 K.
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Free Research Field |
強相関電子物理
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