∼ 2 μm Single Mode Laser Output in Tm3+ Doped Tellurium Germanate Double Claddin

A single-mode laser output of 0.75 W near 2μm was obtained with a slope efficiency of 28.7 with respect to the absorbed pump power when a self-developed double-cladding Tm3+-doped tellurium germanate glass fiber laser was pumped using a 793-nm diode laser. The core glass possesses an infrared cutoff