NONLINEAR ABSORPTION AND PHOTOLUMINESCENCE OF CUCL CRYSTALLITES UNDER SIZE QUANTIZATION OF EXCITONS

Excitonic processes in CuCl nanospheres of mean radius ranging from 20 to 150 angstrom embedded in a glass matrix are investigated. Specific features resulting from quantum confinement are analyzed. Exciton-exciton interaction and relaxing the k-selection rule lead to size-dependent linear and nonlinear optical properties resulting in the light-induced blue shift of excitonic bands, slowing down of radiative decay and drastic changes in the excitation and relaxation dynamics of excitons confined in a quantum box. In addition to the standard classification of the weak (DELTAE(exc) much less than Ry*) and the strong (DELTAE(exc) > Ry*) confinement regime, the peculiarities of the range in which E(LO) less-than-or-equal-to DELTAE(exc) much less than Ry* discussed.