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Quantum Hall effect from the topological surface states of strained bulk HgTe
1Faculty for Physics and Astronomy and Röntgen Center for Complex Material Systems, Universität Würzburg, Am Hubland, D-97074, Würzburg, Germany.
Abstract:
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 semimetallic 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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