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arXiv · 1003.0074

Theoretical Prediction of Topological Insulators in Thallium-based III-V-VI$_2$ Ternary Chalcogenides

Binghai Yan·Chao-Xing Liu·Hai-Jun Zhang·Chi-Yung Yam·Xiao-Liang Qi·Thomas Frauenheim·Shou-Cheng Zhang
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Abstract

We predict a new class of three dimensional topological insulators in thallium-based III-V-VI$_2$ ternary chalcogenides, including TlBiQ$_2$ and TlSbQ$_2$ (Q = Te, Se and S). These topological insulators have robust and simple surface states consisting of a single Dirac cone at the $Γ$ point. The mechanism for topological insulating behavior is elucidated using both first principle calculations and effective field theory models. Remarkably, one topological insulator in this class, TlBiTe$_2$ is also a superconductor when doped with $p$-type carriers. We discuss the possibility that this material could be a topological superconductor. Another material TlSbS$_2$ is on the border between topological insulator and trivial insulator phases, in which a topological phase transition can be driven by pressure.

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Binghai Yan, Chao-Xing Liu, Hai-Jun Zhang, Chi-Yung Yam, Xiao-Liang Qi, Thomas Frauenheim, Shou-Cheng Zhang. 2010-02-27. Theoretical Prediction of Topological Insulators in Thallium-based III-V-VI$_2$ Ternary Chalcogenides. https://doi.org/10.1209/0295-5075%2F90%2F37002

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