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arXiv · 1304.3601

Helical Fermi arcs and surface states in time-reversal invariant Weyl semimetals

Teemu Ojanen
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Abstract

Weyl semimetals are gapless three-dimensional topological materials where two bands touch at even number of points in the Brillouin zone. In this work we study a zincblende lattice model realizing a time-reversal invariant Weyl semimetal. The bulk dynamics is decribed by twelve helical Weyl nodes. Surface states form a peculiar quasi two-dimensional helical metal fundamentally different from the Dirac form typical for topological insulators. Allowed direction of velocity and spin of low-energy surface excitations are locked to the cubic symmetry axes. The studied system illustrates general properties of surface states in systems with common crystal symmetries.

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Teemu Ojanen. 2013-04-12. Helical Fermi arcs and surface states in time-reversal invariant Weyl semimetals. https://doi.org/10.1103/physrevb.87.245112

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