Temperature dependence of transmission loss of chalcogenide glass fibers

The temperature dependence of transmission loss for IR-transmitting chalcogenide glass fibers of sulfur (S)-based, selenium (Se)-based and tellurium (Te)-containing glasses were investigated above room temperature. The influence of temperature on transmission loss significantly depended upon the kind of chalcogen element in the glass. The losses of S-based and Se-based glass fibers were slightly sensitive to temperature. On the other hand, the loss of Te-containing glass fibers increased considerably with temperature. The higher the Te content was, the greater the temperature dependence of transmission loss became. The characteristic behavior of Te-containing glass fibers could be attributed mainly to the additional absorption of due to the increase in the number of thermally excited free carriers with Te content, analogous to Ge and GaAs semiconductors.