Journal de Physique I

Theoretical description of light scattering by a collection of nonlinear Kerr particles

A. J. van Wonderen

Published May 1, 1992• 1 citation

Abstract

We theoretically study multiple scattering of monochromatic light by a collection of spheres that can freely move in a background medium. The spheres contain an optical nonlinearity of the Kerr type. Employing diagrammatic methods we construct the iterative solution of the nonlinear scalar wave equation that describes the electromagnetic radiation field inside the sacttering medium. The ensuing diagrammatic series for the amplitude of the radiation field is averaged over all possible configurations of the scatterers. Subsequently, it is proved that the average amplitude satisfies a nonlinear equation that is the counterpart of the usual Dyson equation. For the case of point scatterers that do not absorb light we obtain solutions of our nonlinear Dyson equation. They predict that as a result of auto-Kerr and backscattering effects, the system can become unstable. Furthermore, we find that it is possible to bleach the scatterers. Finally, the influence of nonlinear absorption on the average amplitude is investigated.

DOI: 10.1051/jp1:1992166

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