Published online by Cambridge University Press: 15 December 1998
Yb3+–Er3+–codoped phosphate glasses have been studied in the context ofresearch for eye-safe laser source near 1540 nm, wavelength corresponding to the4I13/2→4I15/2 Er3+– transition. Undoped and dopedglasses of the composition La2O3–Li2O–P2O5 have been synthesised.Absorption from both the 2F7/2 Yb3+–ground state and the4I15/2 Er3+–ground state, excited state absorption4I13/2→4I9/2 Er3+–transition, emission spectra,decay time measurements and Raman scattering have been investigated by using laserspectroscopic techniques. The Judd-Ofelt intensity parameters Ωt (t = 2, 4, 6)for Er3+ have been calculated in order to determine the radiative lifetimes, thebranching ratios of the transitions and the line strength of the excited stateabsorption 4I13/2→4I9/2. A thermal conductivitymeasurement has also been realised. In this paper, the Mayn spectroscopic properties of Yb3+–Er3+–codopedLaLiP4O12 will be discussed and compared with otherYb3+–Er3+–codoped phosphate glasses.