Photoluminescent properties of vitreous semiconductor systems (GeSe^sub 2^)^sub 1-x^Tl^sub x^ and (GeSe^sub 3^)^sub 1-x^Tl^sub x

The photoluminescence (PL) of glasses of the (GeSe2)1-xTlx and (GeSe3)1-xTlx systems (0 [less than or equal to] x [less than or equal to] 0.1) at T = 77 K is studied. PL spectra of Gaussian shape correspond to intrinsic defects with negative correlation energy. It is found that the shapes of the spectra do not change with the growth in x in the systems. No new emission bands are observed, the PL spectra shift toward lower energies, the intensity of emission falls, and its half-width increases. The kinetics of PL fatigue differs for the two systems and is characterized by a single curve for each, irrespective of the Tl content in the system.