Inverse Faraday Effect in Disordered Two-Dimensional Electronic Systems

I formulate a theory of the inverse Faraday effect in an impure two-dimensional metallic system with lifted spin degeneracy induced by Rashba spin-orbit coupling. Using the formalism of nonequilibrium quantum field theory, the static contributions to the current density up to the second order in powers of the external electromagnetic field are evaluated. For circularly polarized light one of the contributions describes the emergence of static magnetization. It is shown that the direction of induced magnetization may change depending on the frequency of the external radiation and disorder scattering rate. I also find that at large frequencies the leading contribution to the induced magnetization is proportional to the square of the spin-orbit interaction and is inversely proportional to the fifth power of the frequency of an external electromagnetic wave.