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arXiv · 1611.01612

Topological phase in non-centrosymmetric material NaSnBi

Xia Dai·Congcong Le·Xianxin Wu·Shengshan Qin·Zhiping Lin·Jiangping Hu
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Abstract

We predict that a non-centrosymmetric material NaSnBi locates in a three-dimensional non-trivial topological phase under ambient pressure based on first-principle calculations. By deriving the effective model around $Γ$ point, we find that the topological phase transition is driven by a Rashba spin-orbital coupling through an odd number of pairs of band touch because of a small anisotropic gap caused by quintic dispersion terms. In contrast to conventional topological insulators, the spin texture of surface Dirac cone is right-handed and the surface states are strikingly different for different surface terminations.

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Xia Dai, Congcong Le, Xianxin Wu, Shengshan Qin, Zhiping Lin, Jiangping Hu. 2016-11-05. Topological phase in non-centrosymmetric material NaSnBi. https://doi.org/10.1088/0256-307x%2F33%2F12%2F127301

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