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arXiv · 1105.0501

Metacinnabar (β-HgS): a strong 3D topological insulator with highly anisotropic surface states

Franccois Virot·Roland Hayn·Manuel Richter·Jeroen van den Brink
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Abstract

We establish the presence of topologically protected edge states on the (001) surface of HgS in the zinc-blende structure using density-functional electronic structure calculations. The Dirac point of the edge state cone is very close to the bulk valence band maximum. The Dirac cone is extremely anisotropic with a very large electron velocity along one diagonal of the surface elementary cell x' and a nearly flat dispersion in the perpendicular direction y'. The strong anisotropy originates from a broken fourfold rotoinversion symmetry at the surface.

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Franccois Virot, Roland Hayn, Manuel Richter, Jeroen van den Brink. 2011-05-12. Metacinnabar (β-HgS): a strong 3D topological insulator with highly anisotropic surface states. https://doi.org/10.1103/physrevlett.106.236806

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