Exciton emission and energy transport in cadmium sulfide crystals

Abstract It is shown that exciton emission may be used to study detailed energy transport processes in single crystals of cadmium sulfide. The decay time of the exciton emission has been determined to extend from values less than 10 −7 sec at 4·2°K to the microsecond range at room temperature. A delay of the exciton emission produced by the transport of energy through the crystal has been observed. The two mechanisms discussed for the explanation of these results are exciton and ambipolar diffusion at room temperature.