STUDY OF LUMINESCENCE SPECTRA OF SILICA GLASSES BY TIME-RESOLVED TECHNIQUE

The luminescence of low-purity silica glasses irradiated by an N-2 laser (lambda = 337 nm, tau = 9 ns, and P approximate to 10 kW) is studied using the time-resolving technique. The spectrum-shape of the luminescence depends on the location and width of the measuring strobe. The luminescence spectrum with a maximum at 396 nm, which is recorded with the measuring-strobe width of 400 mu S, is identical to the luminescence spectrum excited in the 242-nm absorption band. The N-2 laser is assumed to excite luminescence in the absorption band of germanium centers at 330 nm. This band is not clearly seen in absorption spectra of silica glasses of the II type. At short measuring strobe values (40 ns), the maximum of luminescence spectrum of low-purity glasses is found to be shifted toward the long-wavelength region. In high-purity glasses, no dependence of the luminescence spectrum on time parameters of the recording conditions is observed.