Landau level spectroscopy of valence bands in HgTe quantum wells: Effects of symmetry lowering

Abstract

Landau level spectroscopy has been employed to probe the electronic structure of the valence band in a series of p-type HgTe/HgCdTe quantum wells with both normal and inverted ordering of bands. We find that the standard axial-symmetric 4-band Kane model, which is nowadays widely applied in physics of HgTe-based topological materials, does not fully account for the complex magneto-optical response observed in our experiments - notably, for the unexpected avoided crossings of excitations and for the appearance of transitions that are electric-dipole forbidden within this model. Nevertheless, reasonable agreement with experiments is achieved when the standard model is expanded to include effects of bulk and interface inversion asymmetries. These remove the axial symmetry, and among other, profoundly modify the shape of valence bands.

arXiv comment15 Pages, 11 figures

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Cited by in corpus (6)

• HgCdTe-based quantum cascade lasers operating in the GaAs phonon Reststrahlen band predicted by the balance equations method
• Band structure of a HgTe-based three-dimensional topological insulator
• Unconventional Reentrant Quantum Hall Effect in a HgTe/CdHgTe Double Quantum Well
• Many-particle effects in optical transitions from zero-mode Landau levels in HgTe quantum wells
• Negative polarizability of 2D electrons in HgTe quantum well
• Many-particle hybridization of optical transitions from zero-mode Landau levels in HgTe quantum wells