Laser action in praseodymium doped zinc chloride borophosphate glasses

In order to predict laser action in praseodymium doped zinc chloride borophosphate glasses with the help of laser parameters both absorption and fluorescence spectra have been studied. The glass specimens having composition in mol% B2O3(14.57)–P2O5(44.85)–Na2O(26.08)–ZnCl2(14.50)–Pr6O11(R) (R=0.0, 0.1 and 0.2 mol%) have been prepared by melt quenching technique. The spectra consist of seven absorption bands (400–2400 nm) and three fluorescence bands (400–700 nm). The observed optical spectra are discussed in terms of energy states and the intensity of the transitions. The various energy interaction parameters like Slater–Condon, Landé, Racah and bonding parameters have been computed. Judd–Ofelt intensity parameters and laser parameters have also been calculated. A comparison with phosphate glass shows a considerable increase (by a factor of ∼2.5) in the value of stimulated emission cross-section, σp, of the transition 3P0→3F2 in zinc chloroborophosphate glass.