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arXiv · 1211.5863

Correlated Topological Insulators with Mixed Valence

Feng Lu·JianZhou Zhao·Hongming Weng·Zhong Fang·Xi Dai
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Abstract

We propose the local density approximation (LDA)+Gutzwiller method incorporating Green's function scheme to study the topological physics of correlated materials from the first-principles. Applying this method to typical mixed valence materials SmB6, we found its non-trivial Z2 topology, indicating that SmB6 is a strongly correlated topological insulator (TI). The unique feature of this compound is that its surface states contain three Dirac cones in contrast to most known TIs.

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Feng Lu, JianZhou Zhao, Hongming Weng, Zhong Fang, Xi Dai. 2012-11-26. Correlated Topological Insulators with Mixed Valence. https://doi.org/10.1103/physrevlett.110.096401

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