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arXiv · 1711.01055

Topological phases in Bi/Sb planar and buckled honeycomb monolayers

N. Nouri·M. Bieniek·M. Brzezinska·M. Modarresi·S. Zia Borujeni·Gh. Rashedi·A. Wojs·P. Potasz
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Abstract

We investigate topological phases in two-dimensional Bi/Sb honeycomb crystals considering planar, buckled, freestanding and deposited on a substrate structures. We use the multi-orbital tight-binding model and compare results with density functional theory methods. We distinguish topological phases by calculating topological invariants, analyze edge states of systems in a ribbon geometry and by looking at their entanglement spectra. We show that weak coupling to the substrate of buckled and planar crystals is sufficient to lead to a transition to the $Z_2$ topological insulator phase. Topological crystalline insulator (TCI) phase exhibits a pair of edge states in the semi-infinite geometry and in the entanglement spectrum. Transport calculations for TCI phases show robust quantized conductance even in a presence of symmetry-breaking disorder.

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N. Nouri, M. Bieniek, M. Brzezinska, M. Modarresi, S. Zia Borujeni, Gh. Rashedi, A. Wojs, P. Potasz. 2017-11-03. Topological phases in Bi/Sb planar and buckled honeycomb monolayers. https://doi.org/10.1016/j.physleta.2018.06.037

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