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arXiv · 1912.04818

Many-particle effects in optical transitions from zero-mode Landau levels in HgTe quantum wells

S. S. Krishtopenko·A. M. Kadykov·S. Gebert·S. Ruffenach·C. Consejo·J. Torres·C. Avogadri·B. Jouault·W. Knap·N. N. Mikhailov·S. A. Dvoretskii·F. Teppe
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Abstract

We report on the far-infrared magnetospectroscopy of HgTe quantum wells with inverted band ordering at different electron concentrations. We particularly focus on optical transitions from zero-mode Landau levels, which split from the edges of electron-like and hole-like bands. We observe a pronounced dependence of the transition energies on the electron concentration varied by persistent photoconductivity effect. This is striking evidence that in addition to the already well-documented crystalline and interface asymmetries, electron-electron interactions also have a significant impact on the usual behavior of the optical transitions from zero mode Landau levels.

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S. S. Krishtopenko, A. M. Kadykov, S. Gebert, S. Ruffenach, C. Consejo, J. Torres, C. Avogadri, B. Jouault, W. Knap, N. N. Mikhailov, S. A. Dvoretskii, F. Teppe. 2019-12-10. Many-particle effects in optical transitions from zero-mode Landau levels in HgTe quantum wells. https://doi.org/10.1103/physrevb.102.041404

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