Optically induced defects in vitreous silica

We report the observation of photoluminescence PL. in optically damaged vitreous silica v-SiO2. and its gradual decrease by annealing at temperature range from room temperature to 773 K. Optical damage was induced by tightly focused picosecond or femtosecond irradiation inside v-SiO2. PL bands at 280, 470 and 650 nm were observed. The PL can be excited by 250 nm irradiation, which corresponds to the absorption band of the oxygen vacancy, VO. The decrease of PL with annealing is explained by structural modifications of the defects in the damaged area. q2000 Elsevier Science B.V. All rights reserved