The photoluminescence, optical and physical properties of Sm3+-doped lithium yttrium borate glasses

Lithium yttrium borate glasses doped with samarium ions (LiYBO:Sm3+) were prepared by using melt-quenching for different Sm2O3 concentrations. The spectroscopic properties were investigated by using absorption, emission and decay curve measurements. Density and molar volume of LiYBO:Sm3+ glasses increased with increasing Sm2O3 concentration. The glasses absorbed photons in the visible light (VIS) and near-infrared (NIR) regions. For the photoluminescence property, the glasses showed the strongest emission at 600 nm when they were excited by 403 nm photons. The optimum concentration of Sm2O3 in LiYBO glass is 0.50 mol% which exhibited the highest intensity of emission. The lifetime values decreased with increasing Sm3+ ion concentration which is due to energy transfer through cross-relaxation. The non-exponential decay curves are well fitted by the Inokuti-Hirayama model for S=6, indicating that the interaction for cross-relaxation is of the dipole-dipole type.