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arXiv · 1404.6085

Ab initio study of topological surface states of strained HgTe

Shu-Chun Wu·Binghai Yan·Claudia Felser
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Abstract

The topological surface states of mercury telluride (HgTe) are studied by ab initio calculations assuming different strains and surface terminations. For the Te-terminated surface, a single Dirac cone exists at the $Γ$ point. The Dirac point shifts up from the bulk valence bands into the energy gap when the substrate-induced strain increases. At the experimental strain value (0.3%), the Dirac point lies slightly below the bulk valence band maximum. A left-handed spin texture was observed in the upper Dirac cone, similar to that of the Bi$_2$Se$_3$-type topological insulator. For the Hg-terminated surface, three Dirac cones appear at three time-reversal-invariant momenta, excluding the $Γ$ point, with nontrivial spin textures.

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Shu-Chun Wu, Binghai Yan, Claudia Felser. 2014-04-24. Ab initio study of topological surface states of strained HgTe. https://doi.org/10.1209/0295-5075%2F107%2F57006

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