Scattering and Absorption of Light by a Monolayer of Spherical Particles under Oblique Illumination

The problem of light scattering and absorption by a monolayer of homogeneous spherical particles at an arbitrary angle of incidence of a plane wave, which determines the phase shift between the averaged fields in the particles, has been solved. The solution is based on the quasi-crystalline approximation of the theory of multiple scattering of waves, the mean-field approximation, and the multipole expansion of the fields and the tensor Green function in terms of vector spherical wave functions. Formulas for determining the angular distribution of the incoherently scattered field intensity, the incoherent scattering, absorption, coherent transmission, and reflection coefficients have been derived. The dependences of these characteristics on the direction of illumination are illustrated using partially ordered monolayers of dielectric and semiconductor particles as an example. It is shown that: (i) under oblique illumination the angular distribution of the scattered radiation in azimuthal scattering angle for any polarization of the incident wave (except for p and s ) is asymmetric relative to the plane of incidence, (ii) the maximum of the angular distribution of the radiation transmitted through the monolayer can approach its normal with increasing angle of incidence and/or concentration of particles, (iii) there exist conditions under which the bulk of the scattered radiation is concentrated in the direction opposite to the direction of the incident radiation, and (iv) the dependence of the monolayer absorption coefficient on the illumination angle has extrema whose positions and magnitudes are determined by the polarization of the incident wave.