Structural Dependent Thermal And Optical Properties Of Rare Earth Doped Glass With Mixed Glass Formers

摘要

A series of glasses containing the glass formers, phosphate and tellurite, were prepared by varying the glass composition and rare earth doping concentration. The glass transition temperature T_g decreased with the increase in the Na_2O concentration and increased with phosphate addition. A structural analysis based on FTIR spectra is used to explain the observed changes in T_g. The change in the bandwidth of Er fluorescence peaked around 1534 nm with glass composition and erbium concentration is reported. An analysis of the fluorescence spectra shows that a decrease in TeO_(3-δ), and TeO_3 units present in the phosphate modified glass as compared to the tellurite glass without it. A model is proposed for the local structure of Er doped sodium phosphotellurite glasses. The spectroscopic properties of Er_2O_3 doped and Er_2O_3-Yb_2O_3 codoped sodium phosphotellurite glasses are investigated.