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arXiv · 1701.07523

Searching for Large-gap Quantum Spin Hall Insulators: Boron-Nitride/(Pb, Sn)/{\alpha}-Al2O3 Sandwich Structures

Hui Wang·D. Lu·J. Kim·Z. Wang·S. T. Pi·R. Q. Wu
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Abstract

Topological insulators hold great potential for efficient information processing and storage. Using density functional theory calculations, we predict that a honeycomb lead monolayer can be stabilized on the Al2O3 (0001) substrate and becomes topologically non-trivial with a sizeable band gap (~0.27 eV). Furthermore, we propose to use hexagonal boron-nitride (h-BN) monolayer as a protection for the topological states of Pb/Al2O3 and Sn/Al2O3. Our findings suggest new possibilities for designing and protecting two-dimensional TIs for practical applications.

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Hui Wang, D. Lu, J. Kim, Z. Wang, S. T. Pi, R. Q. Wu. 2017-01-26. Searching for Large-gap Quantum Spin Hall Insulators: Boron-Nitride/(Pb, Sn)/{\alpha}-Al2O3 Sandwich Structures. https://doi.org/10.1039/c7nr00631d

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