Absorption of nonpolarized light by a two-dimensional ensemble of spherical silver particles under oblique illumination

Abstract

The problem of absorption of nonpolarized (natural) light by a two-dimensional ensemble (monolayer) of spherical particles under oblique illumination is considered. The solution is based on the statistical theory of multiple scatteing of waves. The written equations make it possible to find the optimal conditions for the absorption of directed light to increase the absorption efficiency of monolayers with a periodic and partially ordered spatial arrangement of particles. The results of the calculations are presented for the absorption coefficient of polarized and natural light by ensembles of silver particles in a nonabsorbing medium. The particle size and monolayer filling factor are chosen so as to illustrate the dependence of absorption on the angle of incidence under conditions of resonance effects caused by the spatial organization of particles. It is shown that in the region of the resonant absorption peak a normally illuminated monolayer with a triangular lattice of silver particles can absorb almost an order of magnitude more incident light than a partially ordered layer. The absorption coefficient of a monolayer under directional oblique illumination can be almost an order of magnitude larger than under normal illumination. The results can be used to optimize the design of opto-electronic devices based on particulate layers.