A scalable high-power yellow laser source based on frequency doubling of a combined Yb-Raman fiber amplifier

We demonstrate a record of over 20W yellow light by frequency-doubling the output of a novel Yb-doped fiber source. A pulsed source in the wavelength range of 1060-1100nm is efficiently shifted by SRS to the wavelength of a CW seed in the 1100-1180nm range. While pulse width is determined by the pulsed source, the wavelength is set by the narrowband CW seed. The extended frequency is doubled to yellow in a single pass SHG with an overall efficiency of 915nm pump converted to yellow exceeding 25%. The scheme can be used to generate scalable, high-power, costeffective sources in the 560-590nm range.