The emission band of holmium-doped silica fibers extends beyond 2200 nm, which means these lasers have potential of covering considerable parts of the atmospheric transmission window between ∼2100 nm and 2250 nm. However, efficient operation towards 2200 nm is challenging due to absorption in fused silica at the laser wavelength. Here we present a holmium-doped fiber laser specifically targeting long wavelength operation. The laser is implemented as a high-feedback wavelength selective ring

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... ty, and is tunable from 2025 nm to 2200 nm. A maximum slope efficiency of 58 % is obtained at 2050 nm, and a slope of 27 % at 2200 nm. A power of 5.5 W from a single aperture (8.9 W total) is demonstrated at 2200 nm. Our results represent extended coverage of the 2 µm spectral band with multiwatt-level silica fiber lasers.