Composition-dependent spectroscopic properties of Nd 3+-doped tellurite–germanate glasses

Abstract

Nd 3+-doped tellurite–germanate glasses with various compositions were prepared by a conventional melt-quenching method. On the basis of Judd–Ofelt theory, the optical transition intensity parameters Ω λ ( λ=2, 4, 6) of Nd 3+ in all the samples were calculated from the absorption spectra. By using these three intensity parameters, the radiative transition properties, such as the transition rates, branch ratios for 4F 3/2→ 4I 11/2 and 4F 3/2→ 4I 9/2 transitions, and radiative lifetimes of 4F 3/2 level of Nd 3+ in all the glasses were carefully calculated. The compositional dependence of these spectroscopic parameters was analyzed. According to the McCumber theory, the emission cross sections for 4F 3/2→ 4I 9/2 of Nd 3+ in various glasses were obtained, furthermore the optical gain properties for 4F 3/2→ 4I 9/2 transition in all the samples were also studied.