Group 14 element-based non-centrosymmetric quantum spin Hall insulators with large bulk gap

Ma Y, Kou L, Du A, Heine T (2015)

Publication Type: Journal article

Publication year: 2015

Journal

Nano Research Springer Verlag (Germany)

Book Volume: 8

Pages Range: 3412-3420

Journal Issue: 10

DOI: 10.1007/s12274-015-0842-7

Abstract

To date, a number of two-dimensional (2D) topological insulators (TIs) have been realized in Group 14 elemental honeycomb lattices, but all are inversionsymmetric. Here, based on first-principles calculations, we predict a new family of 2D inversion-asymmetric TIs with sizeable bulk gaps from 105 meV to 284 meV, in X2–GeSn (X = H, F, Cl, Br, I) monolayers, making them in principle suitable for room-temperature applications. The nontrivial topological characteristics of inverted band orders are identified in pristine X2–GeSn with X = (F, Cl, Br, I), whereas H2–GeSn undergoes a nontrivial band inversion at 8% lattice expansion. Topologically protected edge states are identified in X2–GeSn with X = (F, Cl, Br, I), as well as in strained H2–GeSn. More importantly, the edges of these systems, which exhibit single-Dirac-cone characteristics located exactly in the middle of their bulk band gaps, are ideal for dissipationless transport. Thus, Group 14 elemental honeycomb lattices provide a fascinating playground for the manipulation of quantum states. [Figure not available: see fulltext.]

Involved external institutions

Jacobs University Bremen gGmbH

Germany (DE) Queensland University of Technology (QUT)

Australia (AU)

How to cite

APA:

Ma, Y., Kou, L., Du, A., & Heine, T. (2015). Group 14 element-based non-centrosymmetric quantum spin Hall insulators with large bulk gap. Nano Research, 8(10), 3412-3420. https://doi.org/10.1007/s12274-015-0842-7

MLA:

Ma, Yandong, et al. "Group 14 element-based non-centrosymmetric quantum spin Hall insulators with large bulk gap." Nano Research 8.10 (2015): 3412-3420.

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