Polarization of light backscattered by wavelength-scale particles

Abstract

We analyze angular dependencies of light scattered by wavelength-scale particles into the backscattering regime, that is, into scattering angles θ ≥ 90°. We consider spherical and cubic particles, oblate and prolate spheroidal particles, as well as clusters of spherical particles, all with equal-volume-sphere size parameters 4 ≤ x ≤ 10 and real-valued refractive indices 1.1 ≤ m ≤ 2.0. We offer interference-based explanations for the angular dependencies of the scattered intensity, degree of linear polarization for unpolarized incident light, and the depolarization ratio.