NARROW-BAND SPECTROSCOPIC SOURCE OF COHERENT RADIATION TUNABLE IN THEMID-IR RANGE

A description is given of a repetitively pulsed source of narrow-band coherent radiation with continuous frequency tuning in the ranges 1.5 -1.85 mu m and 2.5 -3.7 mu m, and with energies per pulse up to 8 and 3 mJ, respectively. The source is based on parametric amplification of a weak IR signal from a difference-frequency generator or from a sing le-mode optical parametric oscillator. This source was used to determi ne the spectra of IR absorption and of degenerate four-wave mixing, as well as the spectra of excitation of stimulated resonance Raman scatt ering of light in some molecules under static or supersonic jet condit ions.