Spectroscopic and thermal properties of Yb3+ doped TeO2-Bi2O3-Nb2O5 based tellurite glasses

Series of (94%-x) TeO2-6% Bi2O3-x Nb2O5 (x=10, 12.5, 15, 17.5 and 20 mol%) glasses doped with Yb2O3 were prepared by the melt-quenching method. Their emission cross-sections, fluorescence lifetimes, gain and thermal properties were investigated by the absorption spectra, the fluorescence decay curves and differential scanning calorimetry (DSC), respectively. The results show that the glass with 15 mol% Nb2O5 possesses the largest emission cross-section of 1.36 pm2, the longest fluorescence lifetime of 0.96 ms and the highest gain coefficient of 1.31 ms pm2; also the glass has excellent thermal properties, for which the value of ∆T (=Tx−Tg) reaches up to 144 °C. These indicate that this tellurite glass may have potential application as Yb2O3 doped gain medium for solid lasers.