The fabrication of Er3+/Ce3+ co-doped tellurite- bismuth glasses and the improvement of spectroscopic properties

A series of 80TeO2-10Bi2O3-10TiO2-0.5Er2O3-xCe2O3 (x=0, 0.25, 0.5, 0.75, 1.0 mol%) and (80-y) TeO2-10Bi2O3-10TiO2-yWO3-0.5Er2O3-0.75Ce2O3 (y=3, 6, 9, 12 mol%) tellurite-bismuth glasses are prepared by the conventional high-temperature melting and annealing method. The absorption spectra of 400-1700 nm, upconversion spectra and 1.53 m band fluorescence spectra under the excitation of 975 nm, the 4I11/2 and 4I13/2 level fluorescence lifetimes of Er3+ under the excitation of 808 nm, and the Raman spectra of doping-free glass samples are measured. Meanwhile, the spectroscopic parameters of Er3+ are calculated and analyzed with the help of Judd-Ofelt theory and McCumber theory. The results indicate that the upconversion fluorescence can be suppressed efficiently and the 1.53 m band fluorescence can be enhanced evidently, owing to the energy transfer from Er3 +: 4I11/2Ce3+:2F5/2 levels when the Ce3+ ions are introduced into the Er3+-doped tellurite-bismuth glasses. Moreover, the 1.53 m band fluorescence intensity can be improved and the fluorescence spectral width can be broadened further when an appropriate amount of WO3 component is introduced. The above research results are of theoretical significance for obtaining the tellurite-bismuth glasses with excellent spectroscopic properties, which are used for the 1.53 m broadband Erbium-doped optical fiber amplifier.