Optical orientation of the carriers in an electron-hole plasma in CdS crystals

The degree of circular polarization of the electron-hole plasma recombination radiation is measured under high power excitation with circular polarized light. Depolarization of the radiation on the high-energy edge of the spectrum is observed in the transverse magnetic field. The experimental results are explained in terms of different populations in the electron and hole spin subbands. The spin disorientation times for electron Tsub(se) and hole Tsub(sh) systems and the life time of the carriers tau in the electron-hole plasma are defined from the Hanle effect and are equal to Tsub(se) = (3 to 5) x 10-12 s, Tsub(sh) = (10 to 15) x 10-12 s and tau = (80 to 120) x 10-12 s. (author)