Year: 2015
Type: article
Abstract: Two-dimensional (2D) topological insulators (TIs) with large band gaps are of great importance for the future applications of quantum spin Hall (QSH) effect. Employing ab initio electronic calculations we propose a novel type of 2D topological insulators, the monolayer (ML) low-buckled (LB) mercury telluride (HgTe) and mercury selenide (HgSe), with tunable band gap. We demonstrate that LB HgTe (HgSe) monolayers undergo a trivial insulator to topological insulator transition under in-plane tensile strain of 2.6% (3.1%) due to the combination of the strain and the spin orbital coupling (SOC) effects. Furthermore, the band gaps can be tuned up to large values (0.2 eV for HgTe and 0.05 eV for HgSe) by tensile strain, which far exceed those of current experimentally realized 2D quantum spin Hall insulators. Our results suggest a new type of material suitable for practical applications of 2D TI at room-temperature.
Source: Scientific Reports
DOI: 10.1038/srep14115
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,690
Funders: National Science Foundation, U.S. Department of Energy, National Natural Science Foundation of China, Natural Science Foundation of Hunan Province, California State University, Northridge, National Key Research and Development Program of China, Specialized Research Fund for the Doctoral Program of Higher Education of China, Division of Materials Research, Basic Energy Sciences, Program for Changjiang Scholars and Innovative Research Team in University, Oak Ridge National Laboratory
Awards: G1009022398, G1677563305, PREM - Computational Research and Education for Emergent Materials, G2345735333, G2792525942, G2975730310, G3175207385, G435955328, G4520441475, G4560199820, G4838927321, 碳化硅纳米颗粒表面石墨烯量子点生长机制与形貌调控的理论研究, G6017888150, G6567591333, G8528581361, 拓扑绝缘体/过渡金属二硫属化合物低维异质结构的第一性原理研究
OpenAlex ID: W2573365875