Polarized scattering by Gaussian random particles under radiative torques

Abstract

We study the internal alignment of a statistical ensemble of Gaussian random ellipsoids with respect to the radiation direction. We solve the rigid body dynamics due to scattering forces and torques, using a numerically exact and efficient T-matrix solver for arbitrary particle shapes and compositions. We then compare the polarization of the aligned ensemble to a randomly oriented ensemble and a perfectly aligned ensemble. We find that the ensemble becomes partially aligned under monochromatic radiation and that the internal alignment has an significant effect on the intensity and polarization of the scattered light.

Rotational Disruption of Nonspherical Cometary Dust Particles by Radiative Torques

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Non-spherical particles in optical tweezers: A numerical solution

“…In previous studies [7,8] we have combined into a single software framework a T-matrix [9] scattering solution for particles of arbitrary shape and composition with an integrator of the equations of motion of the particle. This dynamical response by electromagnetic interactions is hereafter called scattering dynamics.…”