Ferromagnetism in the Hubbard model with Topological/Non-Topological Flat Bands
Strongly Correlated Electrons
2011-05-17 v3 Statistical Mechanics
Abstract
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 nonzero gap. We study the Chern number of the flat bands, and find that it is zero for the first class but can be nontrivial in the second. We also prove that the introduction of on-site Coulomb repulsion leads to ferromagnetism in both the classes.
Cite
@article{arxiv.0907.4564,
title = {Ferromagnetism in the Hubbard model with Topological/Non-Topological Flat Bands},
author = {Hosho Katsura and Isao Maruyama and Akinori Tanaka and Hal Tasaki},
journal= {arXiv preprint arXiv:0907.4564},
year = {2011}
}
Comments
6 pages, 5 figures