Coherent Backscattering Characteristics in Multiple Scattering from Finite Disordered Media

The coherent effects in complex interactions of optical waves with disordered structures result in some recognized effects, including the emergence of enhancement in the backscattering direction known as the Coherent Backscattering (CBS) phenomenon. While this effect is extensively studied in large media with high opacity, in this work, we investigate the emergence of the CBS phenomenon in finite-sized sparse random media through a microscopic numerical wave analysis. The full vectorial picture is considered here, enabling the capture of polarization effects in connection with key parameters such as sample size, density factor, and an absolute number of particles in finite and sparse disordered geometries. We also investigate the behavior of enhancement convergence which is a critical parameter in experimental studies. This capability is available in our investigation through direct ensemble averaging while being inaccessible in other typically implemented techniques that are based on average quantities. Our work paves the way for exploring the CBS effect as a new powerful diagnostic tool to characterize finite sparse geometries with randomized spatial inhomogeneities for scientific and industrial applications.