2.8 μm gain-switched erbium-doped fluoride fiber laser pumped at 1.7 μm

Gain-switched mid-infrared 1 and 7 mol. % erbium-doped fluoride fiber lasers pumped at 1.7 μm were demonstrated. They delivered 2.8 μm pulsed laser with maximum average powers of 306 mW and 390 mW, respectively, corresponding to recorded laser efficiencies of 43.6% and 35.5%. This work exhibits the potential of the 1.7 μm pulsed pumping scheme for gain-switched 2.8 μm erbium-doped fluoride fiber lasers and this pumping scheme paves the way for high-efficient pulsed fiber lasers in the 3 μm region.