Eur. Phys. J. B (2016) 89: 268
https://doi.org/10.1140/epjb/e2016-70454-2

Regular Article

Quantum transport in 3D Weyl semimetals: Is there a metal-insulator transition?

Institut für Physik, Universität Augsburg, 86135 Augsburg, Germany

^a e-mail: ziegler@physik.uni-augsburg.de

Received: 25 July 2016
Received in final form: 17 October 2016
Published online: 7 December 2016

Abstract

We calculate the transport properties of three-dimensional Weyl fermions in a disordered environment. The resulting conductivity depends only on the Fermi energy and the scattering rate. First we study the conductivity at the spectral node for a fixed scattering rate and obtain a continuous transition from an insulator at weak disorder to a metal at stronger disorder. Within the self-consistent Born approximation the scattering rate depends on the Fermi energy. Then it is crucial that the limits of the conductivity for a vanishing Fermi energy and a vanishing scattering rate do not commute. As a result, there is also metallic behavior in the phase with vanishing scattering rate and only a quantum critical point remains as an insulating phase. The latter turns out to be a critical fixed point in terms of a renormalization-group flow.