Time-dependent photoluminescence fatigue-recovery phenomena in germanium sulfide glasses

Abstract

Photoluminescence (PL) fatigue-recovery phenomena in germanium sulfide were investigated, and the temperature dependence of the time-dependent PL intensity for several compositions (Ge_{33.3}S_{66.7}, Ge_{20}S_{80} and Ge_{10}S_{90}) was analyzed. Side-bands were observed and two bands out of them for argon-ion laser excitation, one at 2.25 eV for all compositions and the other extended from 2.15 to 2.45 for Ge_{10}S_{90} especially at the lower temperatures, were used to fully describe the time-dependence.The functional form which is similar to those in the previous report [T. Nakanishi et al., J. Non-Cryst. Solids 354 (2008) 1627] was used and it is extended to account for the effect of side-band at below 30 K for Ge_{20}S_{80} and monotonous decrease of background for Ge10S90.