Electromagnetic Scattering from Two Identical Pseudospheres

Abstract

In an attempt to gain some insight into the problem of how close particles have to be on the average before phase effects become important, we have calculated the cross section and phase matrices for two identical particles as a function of the distance between their centers for both broadside and end-on illumination. We employed the point dipole approximation to build two pseudospherical particles each consisting of 32 dipoles with an effective size parameter of 0.9283 and refractive index of l.54–0.0i.

In regard to cross sections we found that in certain cases several percent deviation from the converged value, which is twice the single particle cross section, could be found up to distances of separation of 25 single particle diameters. The maxima and minima in the cross section curves can be explained in terms of simple interference effects. Also the element P₁₁ of the phase matrix showed a great deal of structure, and the position of maxima and minima could be explained by phase shift analysis.