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Quantum spin Hall insulator with a large bandgap, Dirac fermions, and bilayer graphene analog.

ABSTRACT: The search for room temperature quantum spin Hall insulators (QSHIs) based on widely available materials and a controlled manufacturing process is one of the major challenges of today's topological physics. We propose a new class of semiconductor systems based on multilayer broken-gap quantum wells, in which the QSHI gap reaches 60 meV and remains insensitive to temperature. Depending on their layer thicknesses and geometry, these novel structures also host a graphene-like phase and a bilayer graphene analog. Our theoretical results significantly extend the application potential of topological materials based on III-V semiconductors.

SUBMITTER: Krishtopenko SS

PROVIDER: S-EPMC5930414 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Quantum spin Hall insulator with a large bandgap, Dirac fermions, and bilayer graphene analog.

Krishtopenko Sergey S SS Teppe Frédéric F

Science advances 20180420 4

The search for room temperature quantum spin Hall insulators (QSHIs) based on widely available materials and a controlled manufacturing process is one of the major challenges of today's topological physics. We propose a new class of semiconductor systems based on multilayer broken-gap quantum wells, in which the QSHI gap reaches 60 meV and remains insensitive to temperature. Depending on their layer thicknesses and geometry, these novel structures also host a graphene-like phase and a bilayer gr ...[more]

PMID: 29725617

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