Thermally and Optically Stimulated Luminescence Kinetics with Impeded Carrier Transport

A simplified model of thermally stimulated luminescence (TSL) and optically stimulated luminescence (OSL) kinetics is considered for the case of impeded carrier transport. A response function is obtained for the OSL with transport barrier, being of special interest for the extreme case of saturation mode (when the optical term in the model exceeds all other terms). In this case, the maximum of the response function does not depend on the stimulating light intensity but is proportional to the recombination rate, which in turn, depends on the transport barrier and temperature. A high barrier makes the OSL ineffective, whereas the elevated temperatures can increase OSL response for moderate barriers. If carriers released by light are transferred deeper to the respective energy band, they can overcome the transport barrier during their thermalization, which decreases the temperature required for OSL.