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arXiv · 1503.08978

Persistence of two-dimensional topological insulator state in wide HgTe quantum well

E. B. Olshanetsky·Z. D. Kvon·G. M. Gusev·A. D. Levin·O. E. Raichev·N. N. Mikhailov·S. A. Dvoretsky
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Abstract

Our experimental studies of electron transport in wide (14 nm) HgTe quantum wells confirm persistence of a two-dimensional topological insulator state reported previously for narrower wells, where it was justified theoretically. Comparison of local and nonlocal resistance measurements indicate edge state transport in the samples of about 1 mm size at temperatures below 1 K. Temperature dependence of the resistances suggests an insulating gap of the order of a few meV. In samples with sizes smaller than 10 $μ$m a quasiballistic transport via the edge states is observed.

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E. B. Olshanetsky, Z. D. Kvon, G. M. Gusev, A. D. Levin, O. E. Raichev, N. N. Mikhailov, S. A. Dvoretsky. 2015-03-31. Persistence of two-dimensional topological insulator state in wide HgTe quantum well. https://doi.org/10.1103/physrevlett.114.126802

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