On the influence of strong electric and magnetic fields on spatial dispersion and anisotropy of the optical properties of a semiconductor

Nonperturbative methods were used to construct a single-integral equation for the photon polarization operator in a semiconductor in strong electric and magnetic fields of arbitrary orientations. Spatial dispersion was taken into account. The external field configurations at which its influence could be ignored were found. Asymptotic equations for the field dependences of the absorption coefficient and refractive index were obtained. The neglect of the spin of particles was shown to lead to a fundamentally false idea of magnetic field effects on the optical properties of nonconducting crystals.