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arXiv · 1712.03873

Prediction of a large-gap and switchable Kane-Mele quantum spin Hall insulator

Antimo Marrazzo·Marco Gibertini·Davide Campi·Nicolas Mounet·Nicola Marzari
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Abstract

Fundamental research and technological applications of topological insulators are hindered by the rarity of materials exhibiting a robust topologically non-trivial phase, especially in two dimensions. Here, by means of extensive first-principles calculations, we propose a novel quantum spin Hall insulator with a sizeable band gap of $\sim$0.5 eV that is a monolayer of Jacutingaite, a naturally occurring layered mineral first discovered in 2008 in Brazil and recently synthesised. This system realises the paradigmatic Kane-Mele model for quantum spin Hall insulators in a potentially exfoliable two-dimensional monolayer, with helical edge states that are robust and that can be manipulated exploiting a unique strong interplay between spin-orbit coupling, crystal-symmetry breaking and dielectric response.

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Antimo Marrazzo, Marco Gibertini, Davide Campi, Nicolas Mounet, Nicola Marzari. 2017-12-11. Prediction of a large-gap and switchable Kane-Mele quantum spin Hall insulator. https://doi.org/10.1103/physrevlett.120.117701

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