Raman Suppression in a Kilowatt Narrow-Band Fiber Amplifier

A novel technique to suppress stimulated Raman scattering in a high power narrow-band fiber amplifier is reported. By seeding with a combination of a broadband amplified spontaneous emission seed and a narrowband master oscillator seed, the Raman Stokes components can be reduced about 16 dB at a total output power of 1 kW. Raman suppression results are depicted in a different wavelengths seeding case and the same wavelength seeding case, respectively, with different seed power ratios.