Observation of weak localization of light in a finite slab: Anisotropy effects and light path classification

Abstract

We report on the dependence of enhanced backscattering of light in a random medium on sample thickness, mean free path, and size of scattering centers. Introduction of a new difference technique allows for independent observation of contributions from long and short light paths in a suspension of polystyrene spheres. A new anisotropy effect, which has been found to be most prominent for the smallest particles studied, could be classified as a lower-order multiple-scattering phenomenon.