Abstract

Collision enhanced resonances represent an interesting class of nonlinear-optical processes. They occur because collisional dephasing can rephase quantum mechanical amplitudes that ordinarily cancel out exactly, thereby allowing otherwise unobservable wave-mixing resonances to be seen. This is an especially interesting phenomenon because these resonances are coherent effects that are induced by an incoherent process (collisional dephasing). First predicted¹ in the late 1970s and eventually observed² in 1981, these novel effects have now been seen in a wide variety of four-wave-mixing experiments, ranging from self-focusing to coherent anti-Stokes Raman spectroscopy.

© 1989 Optical Society of America