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arXiv · 1601.03707

Weyl semimetal in ultra-thin film of topological insulator multilayer

S. A. Owerre
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Abstract

In ultra-thin film of topological insulator, the hybridization between the top and bottom surfaces opens an energy gap and forms two degenerate quantum anomalous Hall states, which give rise to a quantum spin Hall state. In this paper, we demonstrate that a Weyl semimetal can be realized in an ultra-thin film of topological insulator heterostructure in a similar way to that of the surface state of a strong three-dimensional (3D) topological insulator studied by Burkov and Balents . We find that the system realizes both 3D quantum anomalous Hall phase and 3D quantum spin Hall phase, and the Weyl nodes occur at zero energy when both time-reversal symmetry and inversion symmetry are explicitly broken by the magnetic field and the structure inversion asymmetry of the thin film.

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S. A. Owerre. 2016-01-14. Weyl semimetal in ultra-thin film of topological insulator multilayer. https://doi.org/10.1088/0953-8984/28/23/235501

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