Optical phase conjugation through translational and rotational diffusive rearrangements of liquid-dispersed microparticles

Optical phase conjugation by degenerate four-wave mixing has been achieved in the cw regime in liquid suspensions of polymer microellipsoids. The results clearly show that particle-number-density gratings and orientational gratings are generated within the suspensions over different ranges of the excitation frequency depending upon the beam polarization configuration and the host-liquid viscosity. The measured parameters are in good agreement with a classical model based on light-induced particle diffusive rearrangements. © 1990 The American Physical Society.