Electrons, optical detrapping

By optically creating carriers with a pulse of above band-gap illumination, then monitoring the subsequent current transient due to thermal detrapping, Hurtes et al (1978) and Fairman et al (1979) were able to apply the DLTS method to bulk, high-resistivity materials. This method, however, is unable to distinguish between electron and hole traps, and the calculation of trap densities is difficult. 

Optical bleaching with F-light produced F centers. It was interpreted by Aceves et al. as detrapping of electrons from vacancies far away from Eu -vacancy dipoles and their retrapping at shallower traps related to vacaneies in the neighborhood of 1—V dipoles. 

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