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arXiv · 1207.4547

Topological antiferromagnetic phase in a correlated Bernevig-Hughes-Zhang model

Tsuneya Yoshida·Robert Peters·Satoshi Fujimoto·Norio Kawakami
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Abstract

Topological properties of antiferromagnetic phases are studied for a correlated topological band insulator by applying the dynamical mean field theory to an extended Bernevig-Hughes-Zhang model including the Hubbard interaction. The calculation of the magnetic moment and the spin Chern number confirms the existence of a non-trivial antiferromagnetic (AF) phase beyond the Hartree-Fock theory. In particular, we uncover the intriguing fact that the topologically non-trivial AF phase is essentially stabilized by correlation effects but not by the Hartree shifts alone. This counterintuitive effect is demonstrated, through a comparison with the Hartree-Fock results, and should apply for generic topological insulators with strong correlations.

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Tsuneya Yoshida, Robert Peters, Satoshi Fujimoto, Norio Kawakami. 2013-03-06. Topological antiferromagnetic phase in a correlated Bernevig-Hughes-Zhang model. https://doi.org/10.1103/physrevb.87.085134

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