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arXiv · 1503.01939

Topological Crystalline Insulator and Quantum Anomalous Hall States in IV-VI based Monolayers and their Quantum Wells

C. Niu·P. M. Buhl·G. Bihlmayer·D. Wortmann·S. Blugel·Y. Mokrousov
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Abstract

Different from the two-dimensional (2D) topological insulator, the 2D topological crystalline insulator (TCI) phase disappears when the mirror symmetry is broken, e.g., upon placing on a substrate. Here, based on a new family of 2D TCIs - SnTe and PbTe monolayers - we theoretically predict the realization of the quantum anomalous Hall effect with Chern number C = 2 even when the mirror symmetry is broken. Remarkably, we also demonstrate that the considered materials retain their large-gap topological properties in quantum well structures obtained by sandwiching the monolayers between NaCl layers. Our results demonstrate that the TCIs can serve as a seed for observing robust topologically non-trivial phases.

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C. Niu, P. M. Buhl, G. Bihlmayer, D. Wortmann, S. Blugel, Y. Mokrousov. 2015-03-06. Topological Crystalline Insulator and Quantum Anomalous Hall States in IV-VI based Monolayers and their Quantum Wells. https://doi.org/10.1103/physrevb.91.201401

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