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arXiv · 1910.07418

Topological Phase Diagram of BiTeX--Graphene Hybrid Structures

Zoltán Tajkov·Dávid Visontai·László Oroszlány·János Koltai
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Abstract

Combining graphene with other novel layered materials is a possible way for engineering the band structure of charge carriers. Strong spin-orbit coupling in BiTeX compounds and the recent fabrication of a single layer of BiTeI points towards a feasible experimental realization of a Kane--Mele phase in graphene-based heterostructures. Here, we theoretically demonstrate the tunability of the topological phase of hybrid systems built from graphene and BiTeX (X = I, Br, Cl) layers by uniaxial in-plane tensile and out-of plane compressive strain. We show that structural stress inherently present in fabricated samples could induce a topological phase transition, thus turning the sample in a novel experimental realization of a time reversal invariant topological insulator.

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Zoltán Tajkov, Dávid Visontai, László Oroszlány, János Koltai. 2019-10-15. Topological Phase Diagram of BiTeX--Graphene Hybrid Structures. https://doi.org/10.3390/app9204330

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