Miniaturized Mid-Infrared All-Fiber Laser at 2.9 μm

We report the first demonstration of a miniaturized mid-infrared all-fiber laser operating at 2.9 μm. The linear laser cavity consists of a 55 cm Ho³⁺:ZBLAN fiber, a home-made 1154 nm Raman fiber laser as pump source, and a fiber end-faced mirror as input mirror. Stable lasing at 2865 nm was achieved with the maximum output power of 67 mW and a slope efficiency of_~48.9%.