Nonlinearities of CuCl Microcrystals

Using a “pump and probe” technique, a strong blue shift and a bleaching is measured of the Z3 excitonic absorption line of CuCl microcrystallites embedded in glass. These effects are attributed to exciton exciton‐interactions. They show a response time shorter than the nanosecond. This seems to be mainly due to a fast non‐radiative decay of the excitonic population, leading to a heating‐up of the microcrystals.