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arXiv · 2111.12019

Massive and topological surface states in tensile strained HgTe

David M. Mahler·Valentin L. Müller·Cornelius Thienel·Jonas Wiedenmann·Wouter Beugeling·Hartmut Buhmann·Laurens W. Molenkamp
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Abstract

Magneto-transport measurements on gated high mobility heterostructures containing a 60 nm layer of tensile strained HgTe, a three-dimensional topological insulator, show well-developed Hall quantization from surface states both in the n- as well as in the p-type regime. While the n-type behavior is due to transport in the topological surface state of the material, we find from 8-orbital k.p calculations that the p-type transport results from massive Volkov-Pankratov states. Their formation prevents the Dirac point and thus the p-conducting topological surface state from being accessible in transport experiments. This interpretation is supported by low-field magneto-transport experiments demonstrating the coexistence of n-conducting topological surface states and p-conducting Volkov-Pankratov states at the relevant gate voltages.

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David M. Mahler, Valentin L. Müller, Cornelius Thienel, Jonas Wiedenmann, Wouter Beugeling, Hartmut Buhmann, Laurens W. Molenkamp. 2021-11-23. Massive and topological surface states in tensile strained HgTe. https://doi.org/10.1021/acs.nanolett.1c02456

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