CONTROL OF EXCITONIC AND ELECTRON–HOLE PROCESSES IN WIDE-GAP CRYSTALS BY MEANS OF ELASTIC UNIAXIAL STRESS

The time-resolved emission spectra and the excitation spectra of the main emissions have been measured for the first time in stressed and unstressed RbI crystals using synchrotron radiation of 10-30 eV at 8 K. It has been shown that the applied elastic uniaxial stress (EUS) offers promise for the separation of the elementary multiplication mechanisms of electronic excitations. A different influence of EUS on the self-trapping of excitons or holes at 8 K has been discussed. The mean free path of free excitons decreases, while that of valence holes increases in a stressed RbI crystal.