Spectroscopic properties of Sm3+-doped lanthanum borogermanate glass

Ultraviolet-visible-near infrared (UV-vis-NIR) absorption and photoluminescence of (25−x) La2O3-25B2O3-50GeO2 glass series have been studied with different concentrations (x=0.1-1.0 wt%) of Sm2O3 as an optically active dopant. The values of Judd-Ofelt (JO) parameters (Ωt) follow the trend Ω2>Ω4>Ω6. Visible emission and decay times from the 4G5/2 level and its relative quantum efficiencies are measured. Intense reddish-orange emission corresponding to 4G5/2→6H7/2 transition has been observed in these glasses under 488 nm excitation. A decrease in the quantum yield is observed with increasing Sm3+ ion concentration beyond 1% doping level.