Fluctuation driven topological Hund insulators
Strongly Correlated Electrons
2013-06-06 v2 Mesoscale and Nanoscale Physics
Abstract
We investigate the role of electron-electron interaction in a two-band Hubbard model based on the Bernevig-Hughes-Zhang Hamiltonian exhibiting the quantum spin Hall (QSH) effect. By means of dynamical mean-field theory, we find that a system with topologically trivial non-interacting parameters can be driven into a QSH phase at finite interaction strength by virtue of local dynamical fluctuations. For very strong interaction, the system reenters a trivial insulating phase by going through a Mott transition. We obtain the phase diagram of our model by direct calculation of the bulk topological invariant of the interacting system in terms of its single particle Green's function.
Cite
@article{arxiv.1211.3059,
title = {Fluctuation driven topological Hund insulators},
author = {Jan Carl Budich and Björn Trauzettel and Giorgio Sangiovanni},
journal= {arXiv preprint arXiv:1211.3059},
year = {2013}
}