980 nm Yb-doped single-mode fiber laser and its frequency-doubling with BIBO

A quasi-three-level Yb-doped single-mode fiber laser at 980 nm by adopting two 0° fiber ends as cavity mirrors generated a total output power of 1.32 W with the slope efficiency of 75.3%. The fiber length was 36.5 cm close to the optimal theoretical fiber length. The corresponding optical conversion efficiency was 66% from the incident pump power at 946 nm to the laser power at 980 nm. Through frequency-doubling with BIBO crystal, a total output power of 15 mW at 490.8 nm was obtained.