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arXiv · 1901.10307

Two-dimension Dirac fermions system in CdHgTe quantum wells

M. L. Savchenko·D. A. Kozlov·Z. D. Kvon·N. N. Mikhailov·S. A. Dvoretsky·B. A. Piot
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Abstract

We report on transport and capacitance spectroscopy study of two kinds of quantum wells, namely Cd$_{0.02}$Hg$_{0.98}$Te and Cd$_{0.06}$Hg$_{0.94}$Te with the thicknesses of 7.4 and 11.5 nm, accordingly. The fraction of Cd was chosen in a way that the both quantum wells are expected to have gapless band structure typical for a Dirac fermions system. We have established that the first quantum well exhibits a massless Dirac fermions system with a quality slightly better then in conventional HgTe quantum wells of critical thickness. Second quantum well exhibits a high-quality two-dimensional topological insulator state with the energy gap of around 10 meV and well-defined edge transport making it as a good candidate for further study and applications of topological insulators.

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M. L. Savchenko, D. A. Kozlov, Z. D. Kvon, N. N. Mikhailov, S. A. Dvoretsky, B. A. Piot. 2019-01-29. Two-dimension Dirac fermions system in CdHgTe quantum wells. https://arxiv.org/abs/1901.10307

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