Highly efficient Er-Yb codoped double-clad fiber amplifier with an Yb-band resonant cavity

摘要

A high-power Er-Yb codoped fiber amplifier (EYDFA) with an Yb-band resonant cavity is investigated. By introducing a linear resonant cavity formed by a pair of high-reflection double-clad fiber Bragg gratings, the Yb-ASE problem of high-power pumped EYDFAs can be resolved and the efficiency of the amplifier can be notably improved. At a pump power of similar to 17 W, an output power of 7.25 W was experimentally achieved. The pump conversion efficiency and slope efficiency relative to the applied pump power are similar to 42.6 and similar to 45.6, respectively. Moreover, due to the gain-clamping effect of the Yb cavity, the gain flatness of the amplifier is also evidently improved.