The nonequilibrium dynamics beyond the linear response of Weyl semimetals is studied after a sudden switching on of a dc electric field. The resulting current is a nonmonotonic function of time with an initial quick increase in polarization current followed by a power-law decay. Particle-hole creation à la Schwinger dominates for long times when the conduction current takes over the leading role with the total current increasing again. The conductivity estimated from a dynamical calculation within a generalized Drude picture agrees with the one obtained from Kubo's formula. The full distribution function of electron-hole pairs changes from Poissonian for short perturbations to a Gaussian in the long perturbation (Landau-Zener) regime. The vacuum persistence probability of high-energy physics manifests itself in a finite probability of no pair creation and no induced current at all times.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Aug 13 2015|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics