Erbium:ytterbium co-doped large-core fiber laser with 297W continuous-wave output power

Abstract

We have demonstrated a high-power and high-efficiency erbium:ytterbium (Er:Yb) co-doped fiber laser that produces 297 W of continuous-wave output at 1567 nm. The slope efficiency with respect to the launched pump power changed from 40% to 19% at higher output power due to the onset of Yb co-lasing at 1067 nm. However, the Yb co-lasing was essential for the suppression of catastrophic pulsation at high pump powers that otherwise results if the Yb band gain is allowed to build up. Spectroscopic characteristics of the fiber and the impact of the Yb co-lasing on the 1567 nm slope efficiency are also discussed