High power, multiwavelength, linearly polarized ytterbium-doped fiber laser based on Sagnac fiber loop mirrors

A dumbbell-shaped ytterbium-doped all-fiber laser based on Sagnac fiber loop mirror was demonstrated in this paper. Stable multiwavelength laser output was obtained through finely tuning the polarization controller under the pump of 976 nm laser diode. The largest output power was 5.13 W with the degree of polarization being 14.19 dB while the power fluctuation was no bigger than 0.02 W under the pump power of 20.4 W. The corresponding power difference was less than 3 dB among all channels in long-term observations.