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arXiv · 1101.0911

Mott Physics and Topological Phase Transition in Correlated Dirac Fermions

Shun-Li Yu·X. C. Xie·Jian-Xin Li
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Abstract

We investigate the interplay between the strong correlation and the spin-orbital coupling in the Kane-Mele-Hubbard model and obtain the qualitative phase diagram via the variational cluster approach. We identify, through an increase of the Hubbard $U$, the transition from the topological band insulator to either the spin liquid phase or the easy-plane antiferromagnetic insulating phase, depending on the strength of the spin-orbit coupling. A nontrivial evolution of the bulk bands in the topological quantum phase transition is also demonstrated.

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Shun-Li Yu, X. C. Xie, Jian-Xin Li. 2011-01-05. Mott Physics and Topological Phase Transition in Correlated Dirac Fermions. https://doi.org/10.1103/physrevlett.107.010401

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