High-power continuous-wave supercontinuum generation in highly nonlinear fibers pumped with high-order cascaded Raman fiber amplifiers.

A novel method for efficient generation of a high-power, equalized continuous-wave supercontinuum source in an all-conventional silica fiber architecture is demonstrated. Highly nonlinear fiber is pumped in its anomalous dispersion region using a novel, high-power, L-band laser. The L-band laser encompasses a sixth-order cascaded Raman amplifier which is pumped with a high-power Ytterbium-doped fiber laser and amplifies a low-power, tunable L-band seed source. The supercontinuum generated 35 W of power with ∼40% efficiency. The supercontinuum spectrum was measured to have a high degree of flatness of better than 5 dB over 400 nm of bandwidth (1.3-1.7 μm, limited by spectrum analyzer range) and a power spectral density in this region of >50  mW/nm. The extent of the SC spectrum is estimated to be up to 2 μm.