We describe the fine structure of Dirac states in HgTe/CdHgTe quantum wells of critical and close-to-critical thickness and demonstrate the formation of an anticrossing gap between the tips of the Dirac cones driven by interface inversion asymmetry. By combining symmetry analysis, atomistic calculations, and k-p theory with interface terms, we obtain a quantitative description of the energy spectrum and extract the interface mixing coefficient. The zero-magnetic-field splitting of Dirac cones can be experimentally revealed in studying magnetotransport phenomena, cyclotron resonance, Raman scattering, or THz radiation absorption.
@article{arxiv.1411.1910,
title = {Split Dirac cones in HgTe/CdTe quantum wells due to symmetry-enforced level anticrossing at interfaces},
author = {S. A. Tarasenko and M. V. Durnev and M. O. Nestoklon and E. L. Ivchenko and Jun-Wei Luo and Alex Zunger},
journal= {arXiv preprint arXiv:1411.1910},
year = {2016}
}