Heavy fermion state inpressme-indumd superconductor studied by the de Haas-van Alphen effect under pressure

压力下德哈斯-范阿尔芬效应研究重费米子态压实超导体

• 批准号: 17540325
• 负责人: SETTAI Rikio
• 金额: $ 2.45万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17540325/
• 关键词: Pressure-induced superconductor; Heavy fermion; Quantum abase transition; Qunatum critical noint; de Haas-van Alphen effect; Fermi surface; 反強磁性; dHvA効果; 圧力; 超伝導; 強相関電子系; 希土類化合物

The f electrons of cerium compounds exhibit a variety of characteristic features including spin and charge orderings, spin and valence fluctuations, heavy-fermions and anisoiropic superconductivity. In cerium compounds, the Rudemran-Kittel-Kasuya-Yosida (RKKY) interaction and the Kondo effect compete with each other. The RKKY interaction enhances the long-range magnetic order, while the Kondo effect quenches the magnetic moments of the localized f electrons. Most of the cerium compounds order antiferromagnetically with the Neel temperature T_N, because the RKKY interaction overcomes the Kondo effect at low temperatures.Recently, a new aspect of cerium and uranium compounds with magnetic ordering has been discovered. When a pressure P is applied to compounds with antiferromagnetic ordering such as CeCu_2Ge_2, CeIn_3, and CePd_2Si_2, T_N reaches zero at the quantum critical pressure Pc, and superconductivity is observed at around P_c. The transition from the magnetically ordered state to the nonmagnetic state under pressure, crossing the quantum critical point, is the most interesting issue in strongly correlated f electron systems.We have depeloped high pressure cells for the de Haas-van Alphen experiment and electrical resistivity measurement which can be rotated in the magnetic fields, and investigated the heavy fermion state including the pressure-induced superconductor, which are summarized as follows ;1. Discovery of the pressure-induced superconductor CeIrSi_3 and CeCoGe_3 and huge upper critical field with strong coupling behavior2. Split Fermi surface due to antisymmetric spin-orbit interaction based on the non-conetrosymmetric crystal structure in CeTX_3 (T : transition metal, X : Si, Ge).3. Pressure-induced heavy-fermion superconductivity in Ce_2Ni_3Ge_5 and CePt_3Si,4. Pressure phase diagram in a ferromagnet CePtAl and an antiferromagnet CeTl_3

铈化合物的f电子表现出各种各样的特征，包括自旋和电荷有序，自旋和价涨落，重费米子和各向异性超导。在铈化合物中，Rudemran-Kittel-Kasuya-Yosida（RKKY）相互作用和Kondo效应相互竞争。RKKY相互作用增强了长程磁序，而Kondo效应淬灭了局域f电子的磁矩。由于RKKY相互作用在低温下克服了Kondo效应，大多数铈和铀化合物都具有反铁磁有序性，其Neel温度为T_N。当压力P作用于CeCu_2Ge_2，CeIn_3和CePd_2Si_2等反铁磁有序化合物时，T_N在量子临界压力Pc处达到零，并在Pc附近观察到超导电性。在强关联f电子系统中，在压力作用下从磁有序态到重费米子态的转变，即越过量子临界点，是最令人感兴趣的问题.我们研制了用于de Haas-van Alphen实验和电阻率测量的高压池，可以在磁场中旋转，并研究了重费米子态，包括压力诱导超导体，其概述如下：1.压致超导体CeIrSi_3和CeCoGe_3的发现以及具有强耦合行为的巨大上临界场2.基于CeTX_3（T：过渡金属，X：Si，Ge）的非对称晶体结构，研究了反对称自旋轨道相互作用导致的费米面分裂. Ce_2Ni_3Ge_5和CePt_3Si，4.铁磁体CePtAl和反铁磁体CeTl_3的压力相图

项目成果

Magnetism and superconductivity in CePt3Si under pressure

CePt3Si 压力下的磁性和超导性

• 发表时间: 2006
• 期刊: J. Phys. Soc. Jpn. 75, suppl.
• 作者: T. Takeuchi;et. al.
• 通讯作者: et. al.

De Haas-van Alphen effect in CeTI_3 under pressure

压力下 CeTI_3 中的德哈斯-范阿尔芬效应

• 发表时间: 2007
• 作者: R.;Settai
• 通讯作者: Settai

A change of the 4f-electron character from localized to itinerant at critical pressure in CeIn3

CeIn3 中临界压力下 4f 电子特性从局域到巡回的变化

• 发表时间: 2005
• 作者: R.;Settai;R. Settai
• 通讯作者: R. Settai

Pressure-Induced Heavy-Fermion Superconductivity in Antiferromagnet CeIrSi3 without Inversion Symmetry

• DOI: 10.1143/jpsj.75.043703
• 发表时间: 2006-04
• 期刊: Journal of the Physical Society of Japan
• 影响因子: 1.7
• 作者: I. Sugitani;Y. Okuda;H. Shishido;Tsutomu Yamada;A. Thamizhavel;E. Yamamoto;Tatsuma D. Matsuda;Y. Haga;T. Takeuchi;R. Settai;Y. Ōnuki

Pressure-Induced Superconductivity in Antiferromagnet CePd5A12

反铁磁体 CePd5A12 中的压力诱导超导性

• 发表时间: 2008
• 期刊: Journal of the Physical Society of Japan 77
• 作者: 富澤 智、水戸 毅;他;水戸毅;水戸 毅;H. Yamagami(11);H. Yamagami(9);H. J. Im;H. Sugawara;F. Honda
• 通讯作者: F. Honda