Inverse Equivalent-Source Techniques for Lossless and Passive Metasurfaces with Non-Canonical Shapes and Geometries

We present the formulation for two lossless and passive metasurface design algorithms that are applicable to (i) transmissive metasurfaces with arbitrary shapes and (ii) cascaded metasurface pairs with arbitrary shapes and alignment geometries. This feature is enabled by basing the algorithms on inverse equivalent-source formulations that rely on integral equations. We demonstrate the validity of the design algorithms by simulating two metasurface problems that include non-canonical metasurface shapes and metasurface pair geometries.