Thepretical Study on electronic Structures of f-electron systems based on LDA+U Method

基于LDA U法的f电子系统电子结构预测研究

• 批准号: 10640345
• 负责人: HARIMA Hisatomo
• 金额: $ 2.37万
• 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: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10640345/
• 关键词: Band Theory; Electronic Structures; f-electron Systems; Local Density Approximation; LDA+U Method; Fermi Surface; Quadruploe Order; Singlet Ground State; f電子系化合物

This project is focused on the role of Coulomb interaction in non-magnetic f-electron systems, particularly quadrupole ordered states and singlet ground states, where the effects of the large Coulomb interaction appear even in the ground states in one-particle picture. Therefore the electronic bandstructures are calculated and compared to the experimental results obtained from the dHvA effects and/or XPS etc. by using the FLAPW source codes developed for the LDA+U method.During the three-year project, the LDA+U method has been generalized to the case including the spin-orbit interaction and the source code has been modified for self-consistent density matrix treatment. It was applied to the singlet ground state in Pr-metal, SmB_6, UPd_3 and PrRu_4P_<12> etc. Then, it has been revealed that there are stable solutions with strong anisotropic f electron charge density in CeRu_2Si_2, UAl_3 and YbB_<12>. Moreover, a preliminary calculation for quadrupole ordered PrPb_3 has been done, showing that the improved LDA+U method can be applied in describing quadrupole ordered states.The conventional LDA calculations have been also performed to investigate the effects expected with the LDA+U method. The electronic bandstructures and Fermi surface of CeIrIn_5, CeRhIn_5, CeCoIn_5 and LaRu_4Sb_<12> etc. are calculated and compared to the experimental results.

该项目的重点是库仑相互作用在非磁性f-电子系统中的作用，特别是四极有序态和单重态基态，其中大库仑相互作用的影响甚至出现在单粒子图像的基态中。因此，我们用LDA+U方法开发的FLAPW源程序计算了电子能带结构，并与dHvA效应和XPS等实验结果进行了比较。在三年的计划中，LDA+U方法被推广到包括自旋轨道相互作用的情况，并对源程序进行了修改，使之适合于自洽密度矩阵处理。应用于Pr金属、SmB_6、UPd_3和PrRu_4P_3等的单重态基态<12>，发现CeRu_2Si_2、UAl_3和YbB_3存在稳定的各向异性强f电子电荷密度的溶液<12>。此外，对PrPb_3四极有序态进行了初步计算，表明改进的LDA+U方法可以用于描述PrPb_3四极有序态，并对LDA+U方法所预期的效应进行了常规的LDA计算。计算了CeIrIn_5，CeRhIn_5，CeCoIn_5和LaRu_4Sb_5等的电子能带结构和费米面<12>，并与实验结果进行了比较。

项目成果

N.Kimura et al.: "Observation of a Main Fermi Surface in UPt_3 Studied by the Haas-van Alphen Effect"Physics of Strongly Correlated Electron Systems, JJAP Series. 11. 41-43 (1999)

N.Kimura 等人：“通过 Haas-van Alphen 效应研究的 UPt_3 主费米面的观察”强相关电子系统物理学，JJAP 系列。

T.Honma et al.: "Magnetic and Fermi Surface Properties of the Ferromagnetic Compound UGa_2"J.Phys.Soc.Jpn.. 69. 2647-2659 (2000)

T.Honma 等：“铁磁化合物 UGa_2 的磁性和费米表面特性”J.Phys.Soc.Jpn.. 69. 2647-2659 (2000)

T.Ebihara et al.: "Heavy Fermions in YbA13 Studied by the de Haas-van Alphen Effect"J.Phys.Soc.Jpn.(印刷中). 69-3. (2000)

T.Ebihara 等人：“通过 de Haas-van Alphen 效应研究 YbA13 中的重费米子”J.Phys.Soc.Jpn（出版中）。

Y.Tokiwa et al.: "Magnetoresistance and Haas-van Alphen Oscillation in USi3"J.Phys.Soc.Jpn.(発表予定).

Y. Tokiwa 等人：“USi3 中的磁阻和 Haas-van Alphen 振荡”J.Phys.Soc.Jpn（待出版）。

D.Aoki et.al.: "de Haas-van Alphen Oscillations and Magnetic Properties of YbPb3 and EuPb3" J.Phys.Soc.Jpn.67-12. 4251-4250 (1998)

D.Aoki 等人：“YbPb3 和 EuPb3 的 de Haas-van Alphen 振荡和磁特性”J.Phys.Soc.Jpn.67-12。