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arXiv · 1510.08644

Photoluminescence spectra of an n-doped (Cd,Mn)Te quantum well: an exemplary evidence for the anisotropy-induced valence-band mixing

A. V. Koudinov·C. Kehl·G. Astakhov·J. Geurts·T. Wojtowicz·G. Karczewski
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Abstract

Photoluminescence spectra of a (001)-Cd0.99Mn0.01Te quantum well were taken with linear-polarization resolution and using an in-plane magnetic field. Because the quantum well contained a two-dimensional electron gas, the spectra consisted of several features. Since the quantum well layer was formed by a diluted magnetic semiconductor, the spectra showed pronounced polarization-dependent transformations when the in-plane magnetic field was applied. In the magnetic field, a 90-degrees rotation of the sample about the surface normal axis resulted in a clearly different spectrum, meaning that the nominally equivalent [110] and [1-10] directions in the sample are not equivalent in fact. But, remarkably, the additional 90-degrees rotations of both the polarizer and the analyzer restored the initial spectrum. This combined invariance regarding simultaneous 90-degrees rotation of the sample and reversal of the polarization configuration was known earlier for spin-flip Raman spectra only. Our present observations are interpreted in terms of the mixing of valence subbands leading to the pseudo-isotropic g-factor of the ground-state holes.

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A. V. Koudinov, C. Kehl, G. Astakhov, J. Geurts, T. Wojtowicz, G. Karczewski. 2015-10-29. Photoluminescence spectra of an n-doped (Cd,Mn)Te quantum well: an exemplary evidence for the anisotropy-induced valence-band mixing. https://arxiv.org/abs/1510.08644

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