Investigation of the kinetics of stimulated emission using four-photon parametric interaction

It is shown that a study of the ultrafast kinetics of low-intensity light pulses may be made using coherent anti- Stokes Raman spectroscopy. The resolution of the method is governed by the pump pulse duration. The second harmonic of a single picosecond neodymium laser pulse was combined with dye radiation in a benzene cell. If the spectrum of the dye radiation overlaps the first Stokes component of Raman scattering of the pump radiation in benzene and if the angle of interaction is 1–2°, amplification of the dye radiation at the frequency of the first Stokes component and formation of the anti-Stokes component are observed. By measuring the intensity of the anti-Stokes component as a function of the delay between the probe and pump pulses, it is possible to determine the duration of the dye radiation.