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arXiv · 1410.4440

One-dimensional Dirac electrons on the surface of weak topological insulators

Alexander Lau·Carmine Ortix·Jeroen van den Brink
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Abstract

We show that a class of weak three-dimensional topological insulators feature one-dimensional Dirac electrons on their surfaces. Their hallmark is a line-like energy dispersion along certain directions of the surface Brillouin zone. These one-dimensional Dirac line degeneracies are topologically protected by a symmetry that we refer to as in-plane time-reversal invariance. We show how this invariance leads to Dirac lines in the surface spectrum of stacked Kane-Mele systems and more general models for weak three-dimensional topological insulators.

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Alexander Lau, Carmine Ortix, Jeroen van den Brink. 2015-02-15. One-dimensional Dirac electrons on the surface of weak topological insulators. https://doi.org/10.1103/physrevb.91.085106

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