Use of a continuous wave Raman fiber laser in graded-index multimode fiber for SRS beam combination

We report using a Raman fiber laser ( RFL) based on a multimode graded-index fiber as a novel method for beam combination of two continuous wave pump beams. Due to stimulated Raman scattering, the RFL generates a Stokes beam which can be up to 300% brighter than the pump beams. Up to 5.8 W of Stokes power is generated with an optical conversion efficiency of 56%. (c) 2007 Optical Society of America.