Splitting of Dirac cones in HgTe quantum wells: Effects of crystallographic orientation, interface-, bulk-, and structure-inversion asymmetry

Abstract

We develop a microscopic theory of the fine structure of Dirac states in $(0lh)$-grown HgTe/CdHgTe quantum wells (QWs), where $l$ and $h$ are the Miller indices. It is shown that bulk, interface, and structure inversion asymmetry causes the anticrossing of levels even at zero in-plane wave vector and lifts the Dirac state degeneracy. In the QWs of critical thickness, the two-fold degenerate Dirac cone gets split into non-degenerate Weyl cones. The splitting and the Weyl point positions dramatically depend on the QW crystallographic orientation. We calculate the splitting parameters related to bulk, interface, and structure inversion asymmetry and derive the effective Hamiltonian of the Dirac states. Further, we obtain an analytical expression for the energy spectrum and discuss the spectrum for (001)-, (013)- and (011)-grown QWs.

8 pages, 5 figures, 1 table

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• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• The Quantum Spin Hall Effect: Theory and Experiment
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• Helical edge and surface states in HgTe quantum wells and bulk insulators
• Fine structure of "zero-mode" Landau levels in HgTe/HgCdTe quantum wells
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Cited by in corpus (4)

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• Electric and spin-valley currents induced by structured light in 2D Dirac materials
• Band inversion transition in HgTe nanowire grown along the [001] direction
• Many-particle hybridization of optical transitions from zero-mode Landau levels in HgTe quantum wells