2.7 μm emission of high thermally and chemically durable glasses based on AlF(3)

AlF(3)-based glasses (AlF(3)-YF(3)-CaF(2)-BaF(2)-SrF(2)-MgF(2)) with enhanced thermal and chemical stability were synthesized and compared with the well-known fluorozirconate glass (ZBLAN). The 2.7 μm mid-infrared emission in the AlF(3)-based glasses was also investigated through the absorption and emission spectra. Both the temperature of glass transition and the characteristic temperatures (ΔT, H(r), k(gl)) of the fluoroaluminate glasses were much larger than those of the ZBLAN glasses. The corrosion phenomenon can be observed by naked-eye, and the transmittance dropped dramatically (0% at 3 μm) when the ZBLAN glass was placed into distilled water. However, the AlF(3)-based glass was relatively stable. The fluoroaluminate glasses possessed large branching ratio (20%) along with the emission cross section (9.4×10(−21) cm(−2)) of the Er(3+):(4)I(11/2)→(4)I(13/2) transition. Meanwhile, the enhanced 2.7 μm emission in highly Er(3+)-doped AYF glass was obtained. Therefore, these results showed that this kind of fluoride glass has a promising application for solid state lasers at 3 μm.