Software metamaterials: Transformation media based multiscale techniques for computational electromagnetics

This paper presents computational models employing special transformation-based media—which we call software metamaterials—for the purpose of enhancing the ability of numerical modeling methods for solving multi-scale electromagnetic boundary value problems involving features with multiple length or frequency scales or both. The multi-scale problems, in general, suffer from difficulties in mesh generation and the number of unknowns due to certain meshing requirements dictated by the fine features of the problem. The underlying idea in this study is to introduce transformation media into the computational domain of the finite element method (or finite difference methods) in order to allow uniform and easy-to-generate meshes by avoiding mesh refinement, and therefore, to develop efficient and simple computer-aided simulation tools. In other words, a virtual equivalent problem is created, which acts like the original problem. The techniques proposed in this paper are validated via several finite element simulations in the context of TMz electromagnetic scattering problems.