A high-power (50-MW), kilohertz, picosecond, mid-IR optical parametric amplifier that is pumped by an amplified Ti:sapphire laser and also produces a fixed-frequency visible pulse is described. Mid-IR pulse energies of 40–55 µJ with 0.6–0.8-ps durations and 35-cm -1 bandwidths are reported in the 3650– 2800-cm -1 range. The combination of picosecond mid-IR and visible pulses is useful for two-color spectroscopies, which require simultaneous time and frequency resolution. To illustrate the above, we present vibrational relaxation data for the polyatomic molecule nitromethane, using time-resolved infrared Raman spectroscopy.
© 1997 Optical Society of America
John C. Deàk, Lawrence K. Iwaki, and Dana D. Dlott, "High-power picosecond mid-infrared optical parametric amplifier for infrared Raman spectroscopy," Opt. Lett. 22, 1796-1798 (1997)