HIGH-POWER BROADLY TUNABLE PICOSECOND IR LASER SYSTEM FOR USE IN NONLINEAR SPECTROSCOPIC APPLICATIONS

We developed a high-power tunable picosecond IR laser system suitable for nonlinear spectroscopic investigations. We employ a Ti:sapphire re generative amplifier that produces 1.9-ps, 17-cm(-1), 800-nm pulses at 1 kHz as a pump source. White-light generation in ethylene glycol and optical parametric amplification in potassium titanyl phosphate are u sed to produce the IR pulses. The tuning range extends from 2.4 to 3.8 mu m in the idler and 1.0 to 1.2 mu m in the signal. A total efficien cy (signal plus idler) as high as 20% was achieved. The spatial, spect ral, and temporal characteristics of the IR beam are presented along w ith vibrational sum-frequency spectra from a glass/octadecyltrichloros ilane/air interface. (C) 1996 Optical Society of America.