Nearly transform-limited femtosecond pulses in the mid-infrared between 2.5 and 4.2 μm are produced by optical parametric amplification. The single-stage parametric amplifier is pumped by a tunable high-power femtosecond Ti:sapphire laser system at a 1-kHz repetition rate and is seeded by quasi-cw radiation from the Q-switched Nd:YLF laser used to pump the regenerative amplifier. The generated idler pulses have a duration comparable with or shorter than the pump pulse duration and energy on the nanojoule to microjoule level. The compression resulting from the temporal gain narrowing permits the generation of sub-100-fs mid-infrared pulses.
© 1995 Optical Society of America
V. Petrov and F. Noack, "Tunable femtosecond optical parametric amplifier in the mid-infrared with narrow-band seeding," J. Opt. Soc. Am. B 12, 2214-2221 (1995)