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arXiv · 1912.05981

Competition of trivial and topological phases in patterned graphene based heterostructures

Zoltán Tajkov·János Koltai·József Cserti·László Oroszlány
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Abstract

We explore the effect of mechanical strain on the electronic spectrum of patterned graphene based heterostructures. We focus on the competition of Kekulé-O type distortion favoring a trivial phase and commensurate Kane-Mele type spin-orbit coupling generating a topological phase. We derive a simple low-energy Dirac Hamiltonian incorporating the two gap promoting mechanisms and include terms corresponding to uniaxial strain. The derived effective model explains previous ab initio results through a simple physical picture. We show that while the trivial gap is sensitive to mechanical distortions, the topological gap stays resilient.

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Zoltán Tajkov, János Koltai, József Cserti, László Oroszlány. 2020-05-06. Competition of trivial and topological phases in patterned graphene based heterostructures. https://doi.org/10.1103/physrevb.101.235146

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