Optical nonlinearities of excitons in CuCl microcrystals

Nonlinear optical properties of excitons in CuCl microcrystals in NaCl host crystals were studied by the absorption saturation method. Prominent absorption saturation of excitons was observed together with a blue shift. Optical nonlinearity was found to increase with an increase in the size of the CuCl microcrystals. The observed nonlinearities are very large compared with those in bulk CuCl crystals and GaAs quantum wells.