Basic Research on Electronic Structure Theory in Magnetic Highly-Correlated Electron Systems

磁强关联电子系统电子结构理论基础研究

• 批准号: 15540352
• 负责人: YAMAGAMI Hiroshi
• 金额: $ 1.47万
• 依托单位: Kyoto Sangyo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15540352/
• 关键词: Highly Correlated Electron System; Electronic Structure; Band Theory; 磁性; f電子系化合物; フェルミ面; 磁気モーメント; 相対論

A renewed results related with electronic structure research on some transuranium compounds, especially their Fermi surfaces, were obtained :1.The Fermi surface and the magnetic moment in an antiferromagnet NpRhGa_5 were calculated using a relativistic spin-polarized band theory including an orbital polarization effect. This material has HoGoGa_5-type crystal structure, and the magnetic moments in the ground state are arranged along the [110] direction with a propagation vector q=[0,0,1/2]. It turned out that the shape of the Fermi surface obtained from the calculations well explains the angular dependence of the frequency branches measured by the de Haas-van Alphen (dHvA) effect. Moreover, the magnitude of the magnetic moment at the Np site is in agreement with the observed value by neutron scattering. It became clear from these calculated results to characterize the 5 f electrons of NpRhGa_5 as an itinerant magnetic electron.2.We investigated whether the same character is maintained to a nonmagnetic Np compound without a spin and an orbital degree of freedom. Although almost all Np compounds are magnetic, NpGe_3 is one of a few nonmagnetic compounds. The Fermi surface of NpGe_3 was calculated by relativistic hand theory. The calculated results give a quantitative agreement of the observed dHvA frequency branches. Furthermore, if an enhancement factor estimated by an electronic specific heat coefficient is taken into consideration, we can compare quantitatively the theoretical values with the experimental values for cyclotron effective mass.3.The first observation of a dHvA frequency in a nonmagnetic Pu compound PuIn_3 was successful in the world. The calculated result by a relativistic band theory was able to show an origin of the measured dHvA frequency branch quantitatively. This success suggested that 5 f electrons in nonmagnetic Pu compound also behave as an itinerant electron.

对某些超铀化合物的电子结构研究，特别是费米面的研究，获得了新的结果：1.采用考虑轨道极化效应的相对论自旋极化能带理论，计算了反铁磁物质NpRhGa_5的费米面和磁矩。该材料具有HoGoGa_5型晶体结构，基态磁矩沿着[110]方向排列，传播矢量q=[0，0，1/2]。结果表明，从计算中得到的费米面的形状很好地解释了由de Haas-van Alphen（dHvA）效应测量的频率分支的角度依赖性。此外，在Np位的磁矩的大小与中子散射的观测值一致。从这些计算结果可以清楚地看出NpRhGa_5的5 f电子是一个巡游磁电子。2.我们研究了没有自旋和轨道自由度的NpRhGa_5的5 f电子是否也具有巡游磁电子的性质。虽然几乎所有的Np化合物都是磁性的，但NpGe_3是少数磁性化合物之一。用相对论手理论计算了NpGe_3的费米面。计算结果给出了所观察到的dHvA频率分支的定量协议。此外，如果考虑到由电子比热系数估算的增强因子，我们可以定量地比较回旋有效质量的理论值和实验值。3.在国际上首次成功地观测到了钚化合物PuIn_3的dHvA频率。用相对论能带理论计算的结果能够定量地说明dHvA频率分支的来源。这一结果表明，在Pu化合物中5 f电子也表现为巡游电子.

项目成果

First Observation of de Haas-van Alphen Effect in PuIn3

首次观察到 PuIn3 中的德哈斯-范阿尔芬效应

• 发表时间: 2005
• 期刊: Journal of the Physical Society of Japan 74
• 作者: D.Aoki;S.Ikeda;Y.Haga;D.Aoki;Dai Aoki;Shugo Ikeda;Yoshinori Haga
• 通讯作者: Yoshinori Haga

Itinerant 5f electrons and the Fermi surface properties in an enhanced Pauli paramagnet NpGe3

增强泡利顺磁体 NpGe3 中的流动 5f 电子和费米表面特性

• 发表时间: 2005
• 期刊: J.Phys.Soc.Jpn. 74・8
• 作者: S.Mori;J.Tokunaga;Y.Horibe;Y.Aikawa;T.Katsufuji;Dai Aoki;Dai Aoki;Dai Aoki;Dai Aoki;青木 大;Dai Aoki;Dai Aoki;Dai Aoki
• 通讯作者: Dai Aoki

Single Crystal Growth and Fermi Surface Properties of Antiferromagnet UPdGa5

反铁磁体 UPdGa5 的单晶生长和费米表面性质

• 发表时间: 2005
• 期刊: Journal of the Physical Society of Japan 74
• 作者: D.Aoki;S.Ikeda;Y.Haga;D.Aoki;Dai Aoki;Shugo Ikeda
• 通讯作者: Shugo Ikeda

Hiroshi Yamagami: "Magnetism and Fermi surface of UGe2"Journal of Physics : Condensed Matter. 15・28. S2271-S2274 (2003)

山上浩：“UGe2 的磁性和费米面”物理学杂志：凝聚态物质 15・28（2003 年）。

Itinerant U5fband states in the layered compoundUFeGa5observed by soft x-ray angle-resolved photoemission spectroscopy

软X射线角分辨光电子能谱观察层状化合物UFeGa5中的巡回U5f带态

• DOI: 10.1103/physrevb.73.125109
• 发表时间: 2006
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: S. Fujimori;K. Terai;Y. Takeda;T. Okane;Y. Saitoh;Y. Muramatsu;A. Fujimori;H. Yamagami;Y. Tokiwa;S. Ikeda;T. Matsuda;Y. Haga;E. Yamamoto;Y. Ōnuki
• 通讯作者: Y. Ōnuki