Continuous wave 184 W thulium-doped fiber laser emitting at 1.95 µm in compact efficient package

We present a single-oscillator Tm-doped fiber laser emitting 184 W at 1.95 μm with 49.4% slope-efficiency, 0.6 nm FWHM at 1949.6 nm. An M² factor is 1.3 at 30% of the maximum output power. We used commercially available fiber components and developed splice optimization technique based on beam diameter monitoring. Compact and efficient polymer-based cooling solution is implemented to aim for industry-friendly application.