Scattering of electromagnetic waves by many thin cylinders: theory and computational modeling

Electromagnetic (EM) wave scattering by many parallel infinite cylinders is studied asymptotically as a tends to 0, where a is the radius of the cylinders. It is assumed that the centres of the cylinders are distributed so that their numbers is determined by some positive function N(x). The function N(x) >= 0 is a given continuous function. An equation for the self-consistent (limiting) field is derived as a tends to 0. The cylinders are assumed perfectly conducting. Formula for the effective refraction coefficient of the new medium, obtained by embedding many thin cylinders into a given region, is derived. The numerical results presented demonstrate the validity of the proposed approach and its efficiency for solving the many-body scattering problems, as well as the possibility to create media with negative refraction coefficients.Comment: 21 pages, 13 figure

Scattering by many small particles and creating materials with a desired refraction coefficient.

Combining an asymptotic method and computational modelling the authors propose a method for creating materials with the desired electrodynamical characteristics, in particular, with a desired refraction coefficient. The problem of wave scattering by many small particles is solved asymptotically under the assumptions ka 1, d a, where a is the size of the particles and d is the distance between the neighbouring particles. On the wavelength one may have many small particles. Impedance boundary conditions are assumed on the boundaries of small particles. The results of numerical simulation show good agreement with the theory. Constructive conclusions are given for creating materials with a desired refraction coefficient on the basis of the obtained numerical results. Engineering realisation of the theory is of practical interest