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Strain induced band inversion and topological phase transition in methyl-decorated stanene film.

ABSTRACT: The researches for new quantum spin Hall (QSH) insulators with large bulk energy gap are of much significance for their practical applications at room temperature in electronic devices with low-energy consumption. By means of first-principles calculations, we proposed that methyl-decorated stanene (SnCH3) film can be tuned into QSH insulator under critical tensile strain of 6%. The nonzero topological invariant and helical edge states further confirm the nontrivial nature in stretched SnCH3 film. The topological phase transition originates from the s-p xy type band inversion at the ? point with the strain increased. The spin-orbital coupling (SOC) induces a large band gap of ~0.24?eV, indicating that SnCH3 film under strain is a quite promising material to achieve QSH effect. The proper substrate, h-BN, finally is presented to support the SnCH3 film with nontrivial topology preserved.

SUBMITTER: Wang D

PROVIDER: S-EPMC5719061 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Strain induced band inversion and topological phase transition in methyl-decorated stanene film.

Wang Dongchao D Chen Li L Liu Hongmei H Shi Changmin C Wang Xiaoli X Cui Guangliang G Zhang Pinhua P Chen Yeqing Y

Scientific reports 20171206 1

The researches for new quantum spin Hall (QSH) insulators with large bulk energy gap are of much significance for their practical applications at room temperature in electronic devices with low-energy consumption. By means of first-principles calculations, we proposed that methyl-decorated stanene (SnCH3) film can be tuned into QSH insulator under critical tensile strain of 6%. The nonzero topological invariant and helical edge states further confirm the nontrivial nature in stretched ...[more]

PMID: 29213076

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