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

Ma, Yandong, Kou, Liangzhi, Du, Aijun, & Heine, Thomas (2015) Group 14 element-based non-centrosymmetric quantum spin hall insulators with large bulk gap. Nano Research, 8(10), pp. 3412-3420.

View at publisher


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.

Impact and interest:

8 citations in Scopus
Search Google Scholar™
9 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 87462
Item Type: Journal Article
Refereed: Yes
Additional URLs:
Keywords: two-dimensional crystal, topological insulators, Dirac states, band inversion, strain engineering, Group 14 honeycomb lattice
DOI: 10.1007/s12274-015-0842-7
ISSN: 1998-0000
Divisions: Current > Schools > School of Chemistry, Physics & Mechanical Engineering
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: © 2015 Tsinghua University Press and Springer-Verlag Berlin
Deposited On: 15 Sep 2015 06:08
Last Modified: 26 May 2016 00:32

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page