Absence of quantization in the circular photogalvanic effect in disordered chiral Weyl semimetals

The circularly polarized photogalvanic effect (CPGE) is studied in chiral Weyl semimetals with short-ranged quenched disorder. Without disorder, the topological properties of chiral Weyl semimetals lead to the quantization of the CPGE, which is a second-order optical response. Using a combination of diagrammatic perturbation theory in the continuum and exact numerical calculations via the kernel polynomial method on a lattice model we show that disorder perturbatively destabilizes the quantization of the CPGE.