Rare-earth-doped cadmium-based chlorofluoride glasses with improved durability

Glass formation is investigated in mixed-halide systems based on CdF₂, NaF, BaF₂, ZnF₂, and CdCl₂. The compositions are optimized for the best compromise between glass stability and low sensitivity to hydrolysis. Addition of 1 mol % rare-earth fluoride does not affect significantly the glass stability. The multiphonon edge is found to depend directly on the chlorine content. Located beyond 9 μm, the position of the IR edge is indicative of low phonon-energy, as compared to pure fluorides. Fundamental vibrations of the host are obtained by means of Raman and far-IR transmission spectroscopies.