Low-noise, high-brightness, tunable source of picosecond pulsed light in the near-infrared and visible.

We have built a flexible source of picosecond pulsed light in both the near-infrared and visible spectral regions. A photonic crystal fiber (PCF) was pumped with a pulsed 1064 nm fiber laser to generate four-wave mixing (FWM) sidebands at 947 nm and 1213 nm. This process was seeded at the idler wavelength with a tunable diode laser to limit the spectral width of the sidebands to less than 0.5 nm. Subsequently the idler was mixed efficiently with the residual pump in a nonlinear crystal to yield their sum frequency at 567 nm. All three outputs were tunable by adjusting the seed wavelength and all had very low pulse-to-pulse amplitude noise. This technique could be extended to different wavelength ranges by selecting different seed lasers and PCF.