Laser operation at 1.2 m in Ho3+-doped ZBYA glass fibers

Powerful 1.2-& mu;m laser operation was produced in Ho3+- doped single-cladding, in-house fabricated ZrF4-BaF2-YF3- AlF3 (ZBYA) glass fibers. The fibers were fabricated based on ZBYA glass with a composition of ZrF4-BaF2-YF3-AlF3. Pumped by an 1150-nm Raman fiber laser, the maximum combined laser output power emitted from both sides of a 0.5-mol% Ho3+-doped ZBYA fiber was 6.7 W, with a slope efficiency of 40.5%. We also observed lasing at 2.9 & mu;m with an output power of 350 mW, which was ascribed to the tran-sition of Ho3+:5I6 & RARR; 5I7. The effect of rare earth (RE) doping concentration and the length of the gain fiber were also inves-tigated to determine their effect on laser performance at 1.2 & mu;m and 2.9 & mu;m. & COPY; 2023 Optica Publishing Group