THE OPTICAL-ABSORPTION AND LUMINESCENCE BANDS NEAR 2 EV IN IRRADIATED AND DRAWN SYNTHETIC SILICA

The annealing behaviors of the 2 ev optical absorption and luminescence and of the various paramagnetic defect centers (E prime , O//2** minus and nonbridging oxygen hole center left bracket NBOHC right bracket ) in irradiated synthetic silica rods and unirradiated drawn fibers have been measured. Good agreement was found between the intensities of the 2 ev absorption and luminescence bands and the sum of the intensities of the hole traps in irradiated Suprasil W, suggesting that the optical transitions in this low OH material might be due to a nonparamagnetic electron trap. However, in Suprasil equally good correlations were observed between the absorption and luminescence and the NBOHC intensity for anneal temperatures above 100 degree C.