Synthesis and infrared spectroscopic properties of Tm3+-doped phosphate glasses

A vitreous domain is investigated in the pseudo-ternary system: P2O5-K2O-CaO-(5Al(2)O(3)). The optimal glass composition has been defined as: 50% P2O5-30% K2O-15% CaO and [(5-x)% Al2O3 +x% Tm2O3]. The Physical and spectroscopic properties of the glass containing 0.75 mol% Tm2O3 are reported. Judd-Ofelt intensity parameters have been determined and compared to those of Tm3+ in other glasses. From the intensity parameters, spontaneous emission probabilities, excited state radiative lifetimes and branching ratios were calculated, The recorded fluorescence spectra have been used to estimate the stimulated emission cross-section of near infrared emissions. Gain cross-section spectrum has been calculated for the F-3(4) -> H-3(6) transition which arises at 1.8 mu m. The results are compared with those obtained for other materials investigated for infrared amplifiers in this spectral range. (C) 2008 Elsevier B.V. All rights reserved.