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arXiv · 1505.03507

Distinct topological crystalline phases in models for the strongly correlated topological insulator SmB6

Pier Paolo Baruselli·Matthias Vojta
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Abstract

SmB6 was recently proposed to be both a strong topological insulator and a topological crystalline insulator. For this and related cubic topological Kondo insulators, we prove the existence of four different topological phases, distinguished by the sign of mirror Chern numbers. We characterize these phases in terms of simple observables, and we provide concrete tight-binding models for each phase. Based on theoretical and experimental results for SmB6 we conclude that it realizes the phase with C^+_{k_z=0}=+2, C^+_{k_z=pi}=+1, C^+_{k_x=k_y}=-1, and we propose a corresponding minimal model.

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Pier Paolo Baruselli, Matthias Vojta. 2015-05-13. Distinct topological crystalline phases in models for the strongly correlated topological insulator SmB6. https://doi.org/10.1103/physrevlett.115.156404

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