Single-frequency Tm-doped fiber laser with 215 mW at 2.05 μm based on a Tm/Ho-codoped fiber saturable absorber

We demonstrate an efficient single-frequency Tm-doped fiber laser at 2050 nm. A ring cavity scheme is employed to boost the net gain at the wavelength. A piece of Tm/Ho-codoped fiber with an absorption coefficient at 2050 nm higher than that of a Tm-doped fiber is used to establish the dynamic Bragg grating for enhancing the frequency selection capability. A single-frequency output of 215 mW is obtained under 2 W of 1570-nm pump power, with the slope efficiency being 22%. To the best of our knowledge, this is the highest single-frequency all-fiber laser oscillator output power above 2 mu m. (C) 2022 Optica Publishing Group

Automated summary

We have demonstrated an efficient single-frequency Tm-doped fiber laser at 2050 nm. By employing a ring cavity scheme and a Tm/Ho-codoped fiber, we have enhanced the frequency selection capability and achieved a high single-frequency output power.