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arXiv · 1307.7191

Topological crystalline Kondo insulators and universal topological surface states of SmB$_6$

Mengxing Ye·J. W. Allen·Kai Sun
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Abstract

We prove theoretically that certain strongly correlated Kondo insulators are topological crystalline insulators with nontrivial topology protected by crystal symmetries. In particular, we find that SmB$_6$ is such a material. In addition to a nontrivial Z$_2$ topological index protected by time reversal symmetry, SmB$_6$ also has nontrival mirror Chern numbers protected by mirror symmetries. On the $(100)$ surface of SmB$_6$, the nontrivial mirror Chern numbers do not generate additional surface states beyond those predicted by the Z$_2$ topological index. However, on the $(110)$ surface, two more surface Dirac points are predicted. Remarkably, we find that for SmB$_6$ both the Z$_2$ topological index and the mirror Chern numbers are independent of microscopic details, which enables us to obtain surface state properties that are universal.

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Mengxing Ye, J. W. Allen, Kai Sun. 2013-07-26. Topological crystalline Kondo insulators and universal topological surface states of SmB$_6$. https://arxiv.org/abs/1307.7191

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