Two-dimensional topological insulators in group-11 chalcogenide compounds: M2Te (M=Cu, Ag)

Ma Y, Kou L, Dai Y, Heine T (2016)

Publication Type: Journal article

Publication year: 2016

Journal

Physical Review B American Physical Society

Book Volume: 93

Article Number: 235451

Journal Issue: 23

DOI: 10.1103/PhysRevB.93.235451

Abstract

Two-dimensional (2D) topological insulators (TIs) are recently recognized states of quantum matter that are highly interesting for lower-power-consuming electronic devices owing to their nondissipative transport properties protected from backscattering. So far, only few 2D TIs, suffering from small bulk band gap (<10meV), have been experimentally confirmed. Here, through first-principles calculations, we propose a family of 2D TIs in group-11 chalcogenide 2D crystals, M2Te(M=Cu,Ag). The nontrivial topological states in Cu2Te and Ag2Te 2D crystals, identified by topological invariant and edge state calculations, exhibit sizeable bulk gaps of 78 and 150 meV, respectively, suggesting that they are candidates for room-temperature applications. Moreover, strain engineering leads to effective control of the nontrivial gaps of Cu2Te and Ag2Te, and a topological phase transition can be realized in Cu2Te, while the nontrivial phase in Ag2Te is stable against strain. Their dynamic and thermal stabilities are further confirmed by employing phonon calculations and ab initio molecular dynamic simulations.

Involved external institutions

Universität Leipzig DE Germany (DE) Queensland University of Technology (QUT) AU Australia (AU) Shandong-University (SDU) CN China (CN)

How to cite

APA:

Ma, Y., Kou, L., Dai, Y., & Heine, T. (2016). Two-dimensional topological insulators in group-11 chalcogenide compounds: M2Te (M=Cu, Ag). Physical Review B, 93(23). https://doi.org/10.1103/PhysRevB.93.235451

MLA:

Ma, Yandong, et al. "Two-dimensional topological insulators in group-11 chalcogenide compounds: M2Te (M=Cu, Ag)." Physical Review B 93.23 (2016).

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