Excitation light source dependence of emission in Sn2+-Ce3+ codoped ZnO-P2O5 glasses

Correlation between excitation light source and the emission property of Sn2+-Ce3+ co-doped zinc phosphate glasses is examined. Although photoluminescence (PL) peaks of both Sn2+ and Ce3+ shifted with increasing amount of Ce3+, there was little energy resonance between Sn2+ and Ce3+ emission centers. On the other hand, radioluminescence (RL) spectra excited by X-ray was independent of the Ce concentration, indicating that emission was mainly observed from Sn2+ emission center. It is expected that energy relaxation process in a RL preferentially occurs in an ns2-type emission center that possesses high transition probability of the excited state in the higher energy region.