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Tuning Edge States in Strained-Layer InAs/GaInSb Quantum Spin Hall Insulators

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 نشر من قبل Tingxin Li
 تاريخ النشر 2016
  مجال البحث فيزياء
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We report on a class of quantum spin Hall insulators (QSHIs) in strained-layer InAs/GaInSb quantum wells, in which the bulk gaps are enhanced by up to five folds as compared to the binary InAs/GaSb QSHI. Remarkably, with consequently increasing edge velocity, the edge conductance at zero and applied magnetic fields manifests time reversal symmetry (TRS) -protected properties consistent with Z2 topological insulator. The InAs/GaInSb bilayers offer a much sought-after platform for future studies and applications of the QSHI.



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