Ferromagnetism in the Hubbard model with topological/non-topological flat bands

被引：67

作者：

Katsura, Hosho ^{[1
,2
]}

Maruyama, Isao ^{[3
]}

Tanaka, Akinori ^{[4
]}

Tasaki, Hal ^{[5
]}

机构：

[1] Univ Calif Santa Barbara, Kavli Inst Theoret Phys, Santa Barbara, CA 93106 USA

[2] RIKEN, Cross Correlated Mat Res Grp CMRG, ASI, Wako, Saitama 3510198, Japan

[3] Osaka Univ, Grad Sch Engn Sci, Osaka 5608531, Japan

[4] Ariake Natl Coll Technol, Dept Gen Educ, Fukuoka 8368585, Japan

[5] Gakushuin Univ Mejiro, Dept Phys, Toshima Ku, Tokyo 1718588, Japan

来源：

EPL | 2010年 / 91卷 / 05期

关键词：

ELECTRON GROUND-STATES; QUANTIZED HALL CONDUCTANCE; BETHE-ANSATZ EQUATIONS; HGTE QUANTUM-WELLS; WAVE-FUNCTIONS; HOFSTADTER PROBLEM; MAGNETIC-FIELDS; BLOCH ELECTRONS; LINE GRAPHS;

D O I：

10.1209/0295-5075/91/57007

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We introduce and study two classes of Hubbard models with magnetic flux or with spin-orbit coupling, which have a flat lowest band separated from other bands by a non-zero gap. We study the Chern number of the flat bands, and find that it is zero for the first class but can be non-trivial in the second. We also prove that the introduction of on-site Coulomb repulsion leads to ferromagnetism in both the classes. Copyright (C) EPLA, 2010

引用

页数：6

共 38 条

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