Study of the Glass Transition Temperature of As-S Glasses for the Fabrication of Chalcogenide Optical Fibers

Values of glass transition temperature (T-g) and of linear expansion coefficient (alpha) for As-x S100-x glasses were measured in the range of concentrations 35 x 42. Because of the importance of the glass formation region 35 x 42 for the optical fibers elaboration, special attention was made on high-pure As-x S100-x glasses. For the glass in the range of 35 x 38, we measure T-g with the interval of x equal to 1 at.% of arsenic. We also measured the T-g values with the interval of x equal to 0.5 at.% of As. We obtained nonlinear behavior of T-g, reflecting the change in molecular composition of As-S glass in the glass composition range studied. The control of such parameters is important to produce optical fibers with specific numerical aperture.