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arXiv · 1806.08847

Spin mixing between subbands and extraordinary Landau levels shift in wide HgTe quantum wells

A. A. Dobretsova·A. D. Chepelianskii·N. N. Mikhailov·Z. D. Kvon
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Abstract

We present both the experimental and theoretical investigation of a non-trivial electron Landau levels shift in magnetic field in wide ~20 nm HgTe quantum wells: Landau levels split under magnetic fields but become degenerate again when magnetic field increases. We reproduced this behavior qualitatively within an isotropic 6-band Kane model, then using semiclassical calculations we showed this behavior is due to the mixing of the conduction band with total spin 3/2 with the next well subband with spin 1/2 which reduces the average vertical spin from 3/2 to around 1. This change of the average spin changes the Berry phase explaining the evolution of Landau levels under magnetic field.

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A. A. Dobretsova, A. D. Chepelianskii, N. N. Mikhailov, Z. D. Kvon. 2018-06-22. Spin mixing between subbands and extraordinary Landau levels shift in wide HgTe quantum wells. https://doi.org/10.1103/physrevb.98.155310

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