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arXiv · 1606.09209

Weyl node with random vector potential

Björn Sbierski·Kevin S. C. Decker·Piet W. Brouwer
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Abstract

We study Weyl semimetals in the presence of generic disorder, consisting of a random vector potential as well as a random scalar potential. We derive renormalization group flow equations to second order in the disorder strength. These flow equations predict a disorder-induced phase transition between a pseudo-ballistic weak-disorder phase and a diffusive strong-disorder phase for sufficiently strong random scalar potential or for a pure three-component random vector potential. We verify these predictions using a numerical study of the density of states near the Weyl point and of quantum transport properties at the Weyl point. In contrast, for a pure single-component random vector potential the diffusive strong-disorder phase is absent.

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Björn Sbierski, Kevin S. C. Decker, Piet W. Brouwer. 2016-06-29. Weyl node with random vector potential. https://doi.org/10.1103/physrevb.94.220202

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