GSTC-based simulation of metasurfaces in finite difference techniques

We propose a simple and robust method for simulating bi-anisotropic metasurfaces as electromagnetic spatial discontinuity problems in the Finite Difference Frequency Domain (FDFD) scheme. The method consists in embedding a numerical version of the Generalized Sheet Transition Conditions (GSTCs) in the finite difference scheme and straightforwardly applies also to the Finite Difference Frequency Domain (FDTD) scheme. This provides a timely solution to the fundamental problem of scattering from an electromagnetic sheet with simultaneous electric and magnetic discontinuities.