Chiral Anomaly and Second Harmonic Generation in Weyl Semimetals

TL;DR

This paper investigates how the chiral anomaly influences second harmonic generation in Weyl semimetals with broken time reversal symmetry, revealing a linear dependence on magnetic field and discussing dominance conditions.

Contribution

It introduces a kinetic equation approach to quantify the chiral anomaly's effect on second harmonic generation in Weyl semimetals.

Findings

Chiral anomaly contribution is linearly proportional to magnetic field.

Chiral anomaly can dominate over Lorentz-type contributions under certain conditions.

The study provides a framework for understanding nonlinear optical responses in Weyl semimetals.

Abstract

We study second harmonic generation in centrosymmetric Weyl semimetal with broken time reversal symmetry. We calculate electric current density at the double frequency of the propagating electromagnetic field in the presence of applied constant magnetic field, using the method of kinetic equation for electron distribution function. It is shown that the chiral anomaly contribution to second harmonic generation in the lowest order is linearly proportional to the applied magnetic field. The limit when the chiral anomaly dominates over the Lorentz-type contribution to second harmonic generation is discussed.