Luminescence characteristics of Nd3+ - doped K-Ba-Al-fluorophosphate laser glasses

Fluorophosphate glasses of composition P2O5 + K2O + KF + BaO + Al2O3 + Nd2O3 (PKFBAN), have been prepared with three (0.1, 1.0 and 2.0 mol%) Nd3+ ion concentrations and their detailed luminescence properties have been investigated. Judd-Ofelt theory has been used to analyse the optical absorption spectrum of 1.0 mol% Nd2O3-doped PKFBAN glass and evaluated the radiative properties. The predicted radiative lifetime of the F-4(3/2) level is found to be 348 mu s, which is slightly larger than the measured lifetime of 286 mu s. The measured lifetime of the F-4(3/2) level is found to decrease from 359 to 227 lis when the Nd2O3 ions concentration is increased from 0.1 to 2.0 mol%. The observed non-exponential nature of the decay curves is attributed to energy transfer between Nd3+ ions through dipole-dipole interaction. The systematic analysis yielded improved laser properties in K-Ba-Al-fluorophosphate glass with respect to those of K-Ba-Al-phosphate glasses.