An iterative solution for TM scattering from perturbed circular dielectric cylinders

The electromagnetic scattering from an infinite-length dielectric cylinder with a nearly homogeneous and circular cross section is considered, with the electric field of the incident plane wave aligned parallel to the infinite axis (TM(z)). An iterative approach is adopted, similar to Born's method, but making use of the Green's function for a perfect circular cylinder. As long as the deviations from a homogeneous circular cylinder are minor, the approach is computationally efficient and accurate, a claim demonstrated by comparisons with a moment-method solution. The issue of convergence is explored with respect to shapes and permittivities of perturbations. A method for a priori determination of the success of the iterative method for arbitrary geometries is also given.