Modeling the angular scattering response of substrated metasurfaces

Metasurfaces enable powerful control of electromagnetic waves, supporting a large variety of applications relevant to the optics community. However, controlling their angular scattering response remains challenging due to the difficulty of achieving angular control with thin films and the absence of accurate modeling tools. Existing techniques cannot simultaneously handle different substrate/superstrate media and higher-order multipolar responses, which are common in dielectric optical metasurfaces. We present a rigorous modeling approach based on generalized sheet transition conditions that incorporates both effects and accurately predicts angular scattering. We demonstrate its use for designing metasurface angular filters that can replace optical 4f systems.