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arXiv · 1101.2627

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

C. Brüne·C. X. Liu·E. G. Novik·E. M. Hankiewicz·H. Buhmann·Y. L. Chen·X. L. Qi·Z. X. Shen·S. C. Zhang·L. W. Molenkamp
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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 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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C. Brüne, C. X. Liu, E. G. Novik, E. M. Hankiewicz, H. Buhmann, Y. L. Chen, X. L. Qi, Z. X. Shen, S. C. Zhang, L. W. Molenkamp. 2011-01-13. Quantum Hall Effect from the Topological Surface States of Strained Bulk HgTe. https://doi.org/10.1103/physrevlett.106.126803

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