94 W 980 nm high brightness Yb-doped fiber laser

We report on the generation of 94 W continuous wave output power at 980 nm using an Yb-doped fiber laser. This is achieved using an ultra large-mode-area rod-type photonic crystal fiber pumped at 915 nm. To the best of our knowledge this is the highest output power close to diffraction-limited beam quality (M-2 about 2.2) achieved in this wavelength range from fibers so far. The experimental results are supported by detailed numerical simulations that provide a deeper understanding of the laser process, in particular the competition with the 1030 nm emission. (C) 2008 Optical Society of America