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Quantum Hall Effect from the Topological Surface States of Strained Bulk HgTe

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 نشر من قبل Christoph Br\\\"une
 تاريخ النشر 2011
  مجال البحث فيزياء
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We report transport studies on a three dimensional, 70 nm thick HgTe layer, which is strained by epitaxial growth on a CdTe substrate. The strain induces a band gap in the otherwise semi-metallic HgTe, which thus becomes a three dimensional topological insulator. Contributions from residual bulk carriers to the transport properties of the gapped HgTe layer are negligible at mK temperatures. As a result, the sample exhibits a quantized Hall effect that results from the 2D single cone Dirac-like topological surface states.



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