Two-watt mid-infrared laser emission in robust fluorozirconate fibers

To the best of our knowledge, we report here the first demonstration of 2.9 µm laser emission from in-house fabricated Ho^3+/Pr^3+ co-doped ZBYA glass fiber. The fiber was fabricated based on the ZBYA glass with compositions of ZrF_4–BaF_2–YF_3–AlF_3–PbF_2–HoF_3-PrF_3. Under the pump of a 1150?nm Raman fiber laser, the maximum unsaturated output power of 2.16 W was obtained in a 15?cm long gain fiber with a slope efficiency of 24%. The influence of rare-earth doping concentration on laser performance was also investigated. The result indicates that ZBYA glass fibers have potential for using as a fluorozirconate glass gain fiber for mid-infrared fiber lasers.