Influence of Nd 3+ concentration on its optical absorption and luminescence properties in potassium borate glass

Spectroscopic and laser properties of Nd 3+ doped potassium borate glass have been studied for different Nd 3+ concentrations ranging from 0.5 to 2.0 mol%. From the absorption spectra, optical band gaps ( E opt ) and various spectroscopic parameters ( E 1 , E 2 , E 3 , ξ 4f and α ) are determined. Using Judd‐Ofelt intensity parameters Ω 2 , Ω 4 and Ω 6 , radiative lifetimes ( τ R ), branching ratios ( β ) and integrated absorption cross sections ( Σ ) have been calculated for certain excited states of Nd 3+ for all the Nd 3+ concentrations. From the spectral profiles of the hypersensitive transition, it is observed that there is slight change in the environment of Nd 3+ ion in different concentrations of Nd 3+ doped potassium borate glass. The radiative lifetimes ( τ R ) for certain excited levels are minimum when the concentration is high. From the emission spectra, peak wavelengths ( λ p ), effective line widths (Δ λ eff ) and stimulated emission cross‐sections ( σ p ) have been obtained for the three transitions 4 F 3/2 → 4 I 9/2 , 4 F 3/2 → 4 I 11/2 and 4 F 3/2 → 4 I 13/2 of Nd 3+ and are compared for different concentrations.