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arXiv · 1807.03598

Spin-orbit splitting of the conduction band in HgTe quantum wells: role of different mechanisms

G. M. Minkov·V. Ya. Aleshkin·O. E. Rut·A. A. Sherstobitov·A. V. Germanenko·S. A. Dvoretski·N. N. Mikhailov
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Abstract

Spin-orbit splitting of conduction band in HgTe quantum wells was studied experimentally. In order to recognize the role of different mechanisms, we carried out detailed measurements of the Shubnikov-de Haas oscillations in gated structures with a quantum well widths from $8$ to $18$ nm over a wide range of electron density. With increasing electron density controlled by the gate voltage, splitting of the maximum of the Fourier spectrum $f_0$ into two components $f_1$ and $f_2$ and the appearance of the low-frequency component $f_3$ was observed. Analysis of these results shows that the components $f_1$ and $f_2$ give the electron densities $n_1$ and $n_2$ in spin-orbit split subbands while the $f_3$ component results from magneto-intersubband oscillations so that $f_3=f_1 - f_2$. Comparison of these data with results of self-consistent calculations carried out within the framework of four-band \emph{kP}-model shows that a main contribution to spin-orbit splitting comes from the Bychkov-Rashba effect. Contribution of the interface inversion asymmetry to the splitting of the conduction band turns out to be four-to-five times less than that for the valence band in the same structures.

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G. M. Minkov, V. Ya. Aleshkin, O. E. Rut, A. A. Sherstobitov, A. V. Germanenko, S. A. Dvoretski, N. N. Mikhailov. 2018-07-10. Spin-orbit splitting of the conduction band in HgTe quantum wells: role of different mechanisms. https://doi.org/10.1016/j.physe.2019.02.007

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