<title>Monte Carlo simulations of the polarization anisotropy in light backscattered from a fractal aggregation</title>

Abstract

This report concerns with investigations on the spatial polarization anisotropy of a backscattered intensity pattern produced at a boundary plane between a scattering medium and surroundings under illumination of a focused laser beam. The investigations are conducted by means of Monte Carlo simulations based on a free pathlength distribution function of the fractal medium, a phase function of the Rayleigh-Debye scattering theory, and a negative-exponential decay of the propagating light by absorption. In this report, we demonstrate numerically the spatial polarization anisotropy of the intensity distribution produced at the boundary plane between the medium and the surroundings, a bow-tie intensity pattern for the co-polarization and a cloverleaf intensity pattern for the cross-polarization, and their dependence on the fractal dimension of the medium. Consequently, we can discuss the validity of our model and algorithm for the fractal medium as the scattering object by studying the dependences of the polarization properties of the multiply- backscattered light on the dimension, the scattering order, and the absorption in comparison with the case of the non- fractal medium.