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arXiv · 1407.4809

Topological Crystalline Insulators and Dirac Octets in Anti-perovskites

Timothy H. Hsieh·Junwei Liu·Liang Fu
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Abstract

We predict a new class of topological crystalline insulators (TCI) in the anti-perovskite material family with the chemical formula A$_3$BX. Here the nontrivial topology arises from band inversion between two $J=3/2$ quartets, which is described by a generalized Dirac equation for a "Dirac octet". Our work suggests that anti-perovskites are a promising new venue for exploring the cooperative interplay between band topology, crystal symmetry and electron correlation.

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Timothy H. Hsieh, Junwei Liu, Liang Fu. 2014-07-17. Topological Crystalline Insulators and Dirac Octets in Anti-perovskites. https://doi.org/10.1103/physrevb.90.081112

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