Abstract

A new innovative single-shot technique to measure the dephasing rate of coherent molecular vibrations and optical phonons in liquids and solids in real time has been developed using Ramaninduced phase conjugation and streak technology. The technique uses two 30-ps pulses at 532 nm intersecting at a small angle. A third <2-ps broadband continuum pulse is directed counterpropagating to one of the 532-nm laser pulses. The signal is scattered in the phase conjugate direction and can be spectrally analyzed with a spectrometer and OMA system and temporally analyzed with a 2-ps resolution streak camera. In a single shot, the spectral output of phase conjugate signals yields the complete Raman spectrum which is phase matched over the bandwidth of the continuum, typically 2000 cm^–1. The temporal response of a particular phonon or molecular vibration is obtained by placing appropriate narrowband filters in front of a streak camera to select the desired Raman frequency component.

© 1987 Optical Society of America