INTENSITY-DEPENDENT DECAY TIMES OF EXCITED ELECTRONS IN SEMICONDUCTOR-DOPED GLASSES

The intensity-dependent decay times of excited electrons in semiconduc tor-doped glasses were measured by using a time-correlated single-phot on counting system. On the basis of the experimental measurements, we propose a simple model based on the surface states, the permanent trap s, and the penetrating and back-scattered electrons in the glasses. An analysis based on our model shows that the photodarkening and the slo w photoluminescence decay were mainly due to the permanent trapping of the penetrating electrons and to the radiative decay of the re-excite d electrons from the traps in the glass, respectively.