Low-Cost Metagratings for Efficient Anomalous Reflection

We develop a rigorous scheme for designing effective metagratings (MGs), sparse composites of subwavelength polarizable particles (meta-atoms), based on low-cost dielectric substrates featuring non-negligible losses. To this end, the common analytical model governing these devices is adapted to consider lossy substrates, and additional degrees of freedom are introduced in order to enhance the device performance. We demonstrate the efficacy of our approach by designing a FR4-based anomalous reflection MG, verified via full-wave simulations. These results pave the path to the realization of efficient beam manipulating low-profile constructs with reduced cost, harnessing the high-fidelity analytical model to provide insight and point out practical avenues to overcome loss limitations in diverse material sets across the electromagnetic spectrum.