High-Energy Passively Mode-Locked Raman Fiber Laser Pumped by a CW Multimode Laser

A passively mode-locked Raman fiber laser based on nonlinear polarization rotation (NPR) with a high nonlinear fiber cavity is proposed and demonstrated. A polarization-independent continuous wave (CW) multimode laser is employed as the pump source in order to avoid stimulated Brillouin scattering generation. This Raman laser generates 890 ps pulses at 1651.3 nm. Under the pump power of 960 mW, the single pulse energy is up to 290.7 nJ with the peak power of 326.7 W. The average output power is up to 110 mW with a conversion efficiency of 11.5%.