Electromagnetic scattering analysis of metamaterials based on non-conformal FEM–BEM–DDM method

The inherent properties of electromagnetic metamaterials, such as their large-scale, periodic, multi-media, and complex geometric structures, make the Finite Element Method with the Domain Decomposition Method (FEM–DDM) an ideal simulation approach. Coupling FEM–DDM with the boundary element method (BEM) can further improve solution accuracy. In this work, an efficient non-conformal FEM–BEM–DDM method for electromagnetic scattering analysis of metamaterials is developed. This method employs FEM–DDM for internal finite-periodic metamaterial modeling, coupled with BEM for open-domain electromagnetic analysis. Moreover, a series of computational techniques have been developed for metamaterial electromagnetic analysis. To minimize computational complexity, non-matching mesh and matrix reuse is implemented at the subdomain interfaces, effectively reducing the solution’s degrees of freedom. An efficient three-level preconditioner and the MLFMA are introduced to optimize the efficiency of iterative solution. The proposed method provides an efficient and accurate framework for electromagnetic scattering analysis of metamaterials.