Femtosecond pulses in the mid-infrared generated by downconversion of a traveling-wave dye laser

Amplified pulses from a colliding-pulse mode-locked dye laser at 620 nm and the output of a femtosecond traveling-wave dye cell are mixed in a LiIO(3) crystal to generate femtosecond pulses in the wavelength range near 5 microm. As much as 10% of the photons from the traveling-wave laser are converted to stable infrared pulses of less than 400-fs duration, 10-nJ energy, and 8-kHz repetition rate.