A combined Yb-Raman fiber amplifier for generating narrow linewidth, high-power pulses in the 1100-1200 nm wavelength range and efficient nonlinear conversion into yellow

We realize a novel scheme for emitting narrow linewidth laser pulses in the 1100-1200 nm wavelength range. A narrowband CW laser at the desired wavelength is combined, together with a broadband pulsed laser at ~1080 nm, into a Large-Mode-Area Ytterbium fiber amplifier. The increase in peak intensity leads to efficient Raman conversion of energy from the amplified 1080 nm pulses into the mode seeded by the CW laser. To demonstrate the concept, a narroband CW diode at 1130 mm and a pulsed broadband laser at 1080 nm are combined to generate >15W pulses at 1130 nm with excellent beam quality and sub-100 pm linewidth, along with a demonstration of high efficiency nonlinear conversion into Yellow (565 nm).