Physical Properties of Multicomponent Fluoride Glasses for Photonic and Superionic Applications

Heavy metal fluoride glasses are promising materials for ultra-low loss mid-infrared optical fibers. The fibers are applied in remote spectroscopy, laser surgery, and thermal imaging. Upon doping with rare earth ions, heavy metal fluoride fibers are suitable for a development of high power laser materials, up-conversion lasers, and optical amplifiers for telecommunications systems. As heavy metal fluorides are prospective fast fluoride ion conductors, fluoride glasses based on ZrF4, BaF2, LaF3, AIF(3) and NaF (ZBLAN), PbF2, InF3, BaF2, AlF3, LaF3 (PIBAL) or ZnF2, BaF2, InF3, SrF2, AlF3, NaF (ZBISAN) are interesting for a development of glassy or fibrous ionic conductors. In this paper, the ionic conductivity and dielectric response of the above-mentioned multicomponent fluoride glasses is studied. The influence of the glass composition on the glass transition temperature (T-g) and on the crystallization temperature (T-cr) is also reported. The optimum composition and drawing temperature for fluoride glass fibers is specified.