Concentration effect on the structural and spectroscopic investigations of Sm3+ ions doped B2O3–Bi2O3–CaF2–Na2O glasses

Abstract A new series of Sm 3+ ions doped sodium fluoroborate glasses have been synthesized following the melt quenching technique. The structural analyses were made recording XRD and FTIR spectra. The XRD pattern reveals the amorphous nature and the FTIR spectra explore the presence of various functional groups such as B–O asymmetric stretching of trigonal BO 3 units, B–O stretching of tetrahedral BO 4 units and vibrations of Bi–O − bond in the BiO 6 octahedral units. The luminescence properties have been explored through UV–vis–NIR, luminescence and decay spectral measurements. The Judd-Ofelt intensity parameters (Ω 2 , Ω 4 , Ω 6 ) were determined from the absorption spectra to investigate the nature of metal-ligand bond and symmetry around the Sm 3+ ion site. In order to elucidate the potential applications of the present Sm 3+ ions doped glasses the radiative properties such as transition probability (A), effective band width (Δλ eff ), stimulated emission cross-section ( σ p E ) and branching ratio (β R ) for the 4 G 5/2 → 6 H 5/2 , 6 H 7/2 , 6 H 9/2 emission levels were determined and compared with the reported literature. The luminescence quenching for the prominent 4 G 5/2 → 6 H 7/2 emission transition have been observed while increasing the Sm 3+ ions concentration beyond 0.5 wt%. The decay rates for the 4 G 5/2 level of the Sm 3+ ions exhibit non-exponential behavior for all the prepared glasses except for the 0.05 wt% Sm 3+ glass and fitted to Inokuti-Hirayama model to understand the predominant energy transfer mechanism takes place among the Sm 3+ ions. It is observed from the determined stimulated emission cross-section and branching ratio values that, of all the studied glasses CNFB0.5S glass can be used as a potential candidate for the development of reddish-orange lasers.