DYNAMICS AND MECHANISMS OF OPTICAL NONLIN EARITIES OF GLASSES DOPED WITH SEMICONDUCTOR CRYSTALLITES IN A STRONGLY CONFINED FLOW

In semiconductor doped glasses, the carriers are three-dimensionaly co nfined and caracterized by discrete energy levels. Our absorption spec tra for CdSe samples are in good agreement with theoretical calculatio ns taking into account the valence band mixing due to the quantum conf inement. Time-resolved luminescence experiments show that the dynamics is dominated by the Anger effect at high excitation fluence. We now s tudy the resonant susceptibility by frequency-resolved four wave mixin g experiments. We observe a resonance consistent with a saturation of the first electronic transition or a mechanism implying trapped carrie rs through a static Kerr effect.