Optical and NIR luminescence spectral studies: Nd3+-doped borosilicate glasses

Nd3+-doped borosilicate glasses with molar composition 20B2O3+ (45-x) SiO2 +20K2CO3+5Na2CO3+10LiF + xNd2O3 were prepared by conventional melt-quenching technique. Structural and optical properties of the proposed glasses were studied using XRD, FTIR, UV–Visible absorption, excitation and NIR emission spectroscopy. Judd-Ofelt theory was applied to the absorption spectrum of 1.0 mol% Nd3+-doped borosilicate glass to estimate the JO intensity parameters (Ω2, Ω4, Ω6). From this theory, various radiative properties like radiative transition probabilities (AT), branching ratios (βr) and stimulated emission cross section (σemi) were determined and reported. The measured lifetimes for theF3/24 level were decreased with increase in Nd3+ concentrations. Moreover, the optical energy gap was calculated for direct and indirect optical transitions. The higher stimulated emission cross section (5.84622 × 10−20 cm2), optical gain (142.64 × 10−25 cm2s), quantum efficiency (77%), and low threshold (1.71 W/m2) indicate that 1.0 mol% Nd3+-doped borosilicate glass could be potential gain medium for solid state NIR laser application at 1.06 μm.