Optical absorption, fluorescence and decay properties of Pr3+-doped PbO-H3BO3-TiO2-AlF3 glasses

Spectroscopic and laser properties of PbO-H3BO3-TiO2-AlF3 glasses doped with 0.1, 0.5, 1.0 and 2.0 mol% of Pr6O11 have been studied. Optical absorption spectra were recorded in the UV-vis-NIR regions and the observed absorption bands were assigned to different electronic transitions from 3H4 ground state of 4f2 configuration. The three phenomenological Judd-Ofelt (J-O) parameters Ωt (t=2, 4, 6) were determined from the measured oscillator strengths by including as well as excluding the 3H4→3P2 hypersensitive transition in J-O analysis. The emission characteristics such as stimulated emission cross-sections (σe), measured branching ratios (βm), measured lifetimes (τm), quantum efficiencies (η) and gain parameters (σe×τm) have been evaluated for the principal intermanifold transitions of Pr3+ from the 3P0 and 1D2 states to the lower lying manifolds in the visible region. From the emission and decay measurements, the effect of Pr3+ ion concentration on the quenching of the 1D2 measured lifetimes has been discussed.