Bistable Beam Splitting in Nonlinear Metagratings

We present an analytical model for the response of a beam-splitting metagrating (MG) comprised of thin wires loaded by nonlinear capacitors. Through rigorous formulation, we reveal that a bistable switching response may emerge in such a configuration, and identify analytically the parameters governing its formation. We show that by judicious choice of these structural and electromagnetic MG parameters, a distinct hysteresis loop may be observed, switching between high specular reflection to high split efficiency, depending on the input field intensity and history of excitation. These results, verified via full-wave simulations, lay the grounds for the development of MG-based electromagnetic switches for communication and analog computing, while establishing the foundations for analysis and synthesis of advanced nonlinear MGs in the future.