Yb-free Er-doped all-fiber amplifier cladding-pumped at 976 nm with output power in excess of 100 W

Abstract : In this paper we present results on power scaling of Er-doped fiber amplifier pumped by multimode diodes at 976 nm. Using an optimized active fiber design including a 34 μm single-mode core with proper Er3+ and co-dopant concentrations we obtained an output power of 103 W at 1585 nm for a pump conversion efficiency of 37 % in an amplifier scheme. To the best of our knowledge the output power is the highest power ever reported for Er-doped fiber lasers pumped at 976 nm