Chiral anomaly and classical negative magnetoresistance of Weyl metals

We consider the classical magnetoresistance of a Weyl metal in which the electron Fermi surface possesses nonzero fluxes of the Berry curvature. Such a system may exhibit large negative magnetoresistance with unusual anisotropy as a function of the angle between the electric and magnetic fields. In this case the system can support an additional type of plasma wave. These phenomena are consequences of the chiral anomaly in electron transport theory.

Figure 1

Schematic three-dimensional electron spectrum in a Weyl metal. Only two valleys in the electron spectrum are shown. The dashed line indicates the direction of the electron spectral flow in the presence of parallel electric and magnetic fields.

Figure 2

Schematic electron spectrum of a Weyl metal in the ultraquantum limit. $n=0,1$ label Landau levels. The dashed line indicates the direction of the electron spectral flow in $p_z$ space in the presence of a $z$ component of the electric field.