Thermal and optical properties of Nd3+ ions in K-Ca-Al fluorophosphate glasses

Fluorophosphate glasses of composition (P2O5-K2O-Al2O3-CaO-CaF2)-doped with various Nd2O3 concentrations were prepared by a melt quenching technique and their thermal, vibrational and optical properties were investigated. Thermal stability of the fluorophosphate glass has been determined from differential scanning calorimetric thermograph. The vibrational modes of the present glass have been studied using Raman spectrum. The intensity parameters, Ωλ (λ=2, 4 and 6) as well as radiative properties for the 4F3/2 level of Nd3+ ion, have been evaluated from the absorption spectra of 1.0 mol% Nd2O3-doped glass using the Judd-Ofelt theory. Strong near infrared emission at 1.06 =m attributed to 4F3/2→4I11/2 transition has been obtained for all the glasses upon 806 nm diode laser excitation. Decay analysis has been carried out and found that the lifetime for the 4F3/2 level of Nd3+ ion was found to be higher compared to the other Nd3+-doped glass host matrices. The quantum efficiency and saturation intensity have been determined to be 93% and 2.32×108 W/m2, respectively for 1.0 mol% Nd2O3-doped glass. The results indicate that the present glasses could be useful for 1.06 µm laser applications.