Formulation and implementation of boundary integral equations for scattering by doubly periodic plasmonic and dielectric structures of infinite lateral extent

We describe a surface integral-equation (SIE) method suitable for reliable computation of electromagnetic fields scattered by 2D-periodic plasmonic and dielectric structures. In particular we present an efficient technique to incorporate objects that are infinite in one or both directions of periodicity. The proposed method uses fast evaluation of the 2D quasi-periodic Green function to build the integral operators defined on the inside of the objects. In a case study the method is used to compute the reflection coefficients for a plane wave incident field impinging on a 2D-periodic array of holes in a metal layer.