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.