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arXiv · 1701.07526

Possibility of Realizing Quantum Spin Hall Effect at Room Temperature in Stanene/Al2O3(0001)

Hui Wang·S. T. Pi·J. Kim·Z. Wang·H. H. Fu·R. Q. Wu
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Abstract

Two-dimensional quantum spin Hall (QSH) insulators with reasonably wide band gaps are imperative for the development of various innovative technologies. Through systematic density functional calculations and tight-binding simulations, we found that stanene on α-alumina surface may possess a sizeable topologically nontrivial band gap (~0.25 eV) at the Γ point. Furthermore, stanene is atomically bonded to but electronically decoupled from the substrate, providing high structural stability and isolated QSH states to a large extent. The underlying physical mechanism is rather general, and this finding may lead to the opening of a new vista for the exploration of QSH insulators for room temperature device applications.

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Hui Wang, S. T. Pi, J. Kim, Z. Wang, H. H. Fu, R. Q. Wu. 2017-01-26. Possibility of Realizing Quantum Spin Hall Effect at Room Temperature in Stanene/Al2O3(0001). https://doi.org/10.1103/physrevb.94.035112

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