Tunable femtosecond pulses in the ultraviolet, generated by upconversion of a traveling-wave dye laser

Abstract

We report the generation of 200-fs pulses with 300-nJ energy; the pulses are tunable in the UV spectral range. Amplified pulses from a colliding-pulse mode-locked dye laser at 620 nm and the output of a femtosecond traveling-wave dye laser (TWDL) are mixed in a nonlinear crystal. Wavelength tuning is achieved by changing the phase-matching angle, which results in upconversion of different spectral components of the broadband output of the dye laser. Approximately 15% of the photons from the TWDL are converted into the UV