MECHANISMS OF PHOTOBLEACHING OF 5 EV OPTICAL-ABSORPTION BAND IN HYDROGEN LOADED GE-DOPED SIO2

Photo-induced effects in H-2 loaded 1GeO(2):9SiO(2) glass were studied . The intensity of the absorption band at 5.14 eV was reduced with UV illumination. The neutral oxygen vacancy and also the Gr lone pair cen ters are reduced with the illumination. There is a one-by-one correlat ion between the reduction of Ge lone pair centers and the generation o f Ge-E' center. We propose that a Ge lone pair center reacts with H-2 molecules in glass to generate a Ce-E' center.