Dynamic Beam Steering with Reconfigurable Metagratings

Metagratings have recently shown promising features for wavefront manipulation, overcoming the efficiency limitations of gradient metasurfaces and their demanding fabrication requirements. Extreme functionalities, such as perfect anomalous reflection and refraction, focusing, and holography, have been proposed and tested. However, most of the developed analytical models concern the manipulation of the reflected field. In this article, we present a theoretical formulation that allows a complete manipulation of both reflected and transmitted fields through a metagrating consisting of arrays of capacitively loaded strips. In addition, the proposed solution enables the design of electronically reconfigurable metagratings for the dynamic control of the diffraction pattern at microwave frequencies. The theoretical formulation is numerically validated and a possible practical implementation of the metagrating is also discussed, as well as the effects of losses and parasitic reactances.