A simple extension of a commercial laser system permits the generation of intense femtosecond infrared pulses near 3 µm by optical parametric generation and amplification at kilohertz repetition rates. Pulse durations of a few hundred femtoseconds and pulse energies of tens of microjoules can be routinely produced, thus permitting nonlinear optical studies of molecular vibrations.

doi.org/10.1364/JOSAB.14.001480
J. Opt. Soc. Am. B
Ultrafast Spectroscopy

Emmerichs, U., Woutersen, S., & Bakker, H. (1997). Generation of intense femtosecond optical pulses around 3 µm with a kilohertz repetition rate. J. Opt. Soc. Am. B, 14, 1480–1483. doi:10.1364/JOSAB.14.001480