Engineering diffraction with analytically designed metagratings

We report analytical methodologies for synthesis of planar devices for perfect beam deflection, based on periodic arrays of printed capacitors (meta-atoms). These so called meta-gratings (MGs) were shown to facilitate efficient anomalous reflection by tuning the capacitor width and position such that the spurious (specular) reflection is cancelled, and all of the incoming power is coupled to the desirable (1st-order) Floquet-Bloch mode. In this talk we present two advancements with respect to previous work. First, we incorporate a supporting substrate into the analytical model, allowing rigorous design of realistic printed-circuit-board (PCB) MGs for perfect anomalous reflection. Second, we extend the MG concept to include multiple meta-atoms per period, enabling control of multiple diffraction modes, implementing perfect anomalous refraction and focusing. Importantly, all physical designs, verified via full-wave simulations, are obtained without any optimization in commercial solvers, demonstrating the efficiency and reliability of the proposed schemes for developing advanced diffraction engineering surfaces.