Observation of exchange interaction effects at optical orientation of excitons in AlGaAs

The exciton luminescence in the AlGaAs layers by the interzonal excitation through the circular-polarization light is studied. The peaks, positioned symmetrically relative to the H = 0 point, are identified on the luminescence depolarization curves in the lateral magnetic field. It is shown, that the above effect is caused by the intersection of the thin structure levels in the magnetic field. The value of the voluminous levels splitting of the voluminous exciton as well as the recombination and spin relaxation times are determine on the basis of the comparison of the theoretical and experimental dependences