Spin polarization and relaxation in a semiconductor with impurity absorption of circularly polarized light

The approach based on kinetic equations is used to describe spin polarization of conduction electrons in a semiconductor doped with d or f atoms and subject to circularly polarized radiation. In the stationary state we find analytical expressions for the spin polarization of band electrons,rho(e), and spin polarization of electrons in the impurity levels, rho(i). It is shown that the degree of spin polarization of the band electrons is mainly determined by the polarization type of the light. On the basis of numerical results we conclude that rho(e) and rho(i) are practically independent of the long- term relaxation processes in the subsystem of magnetic impurities.