25 W Raman-fiber-amplifier-based 589 nm laser for laser guide star.
We report on a 25 W continuous wave narrow linewidth (< 2.3 MHz) 589 nm laser by efficient (> 95%) coherent beam combination of two narrow linewidth (< 1.5 MHz) Raman fiber amplifiers with a Mach-Zehnder interferometer scheme and frequency doubling in an external resonant cavity with an efficiency of 86%. The results demonstrate the narrow linewidth Raman fiber amplifier technology as a promising solution for developing laser for sodium laser guide star adaptive optics.
Feng
Yan
Y
European Southern Observatory, Karl-Schwarzschildstr 2, D-85748 Garching, Germany. yfeng@eso.org
Taylor
Luke R
LR
Calia
Domenico Bonaccini
DB