Absorption and emission properties of Nd3+ in lithium cesium mixed alkali borate glasses

Lithium cesium mixed alkali borate glasses of the composition 67B2O3·xLi2O·(32−x)Cs2O (where x=8, 12, 16, 20 and 24) containing 1 mol% Nd2O3 were prepared by melt quenching. The absorption spectra of Nd3+ were studied from the experimental oscillator strengths and the Judd-Ofelt intensity parameters were obtained. The intensity parameters are used to determine the radiative decay rates (emission probabilities of transitions) (AT), branching ratios (β) and integrated absorption cross-sections (Σ) of the Nd3+ transitions from the excited state J manifolds to the lower lying J′ manifolds. Radiative lifetimes (τR) are estimated for certain excited states of Nd3+ in these mixed alkali borate glasses. Luminescence spectra were measured and the emission cross-sections (σp) were evaluated for the three emission transitions. The variation of luminescence intensity with x was recorded for the three transitions at different excitation power to see the effect of mixed alkalies in these borate glasses.