Low-loss metasurfaces based on discretized meta-atoms

Abstract Metasurfaces are established tools for manipulating light and enhancing light-matter interactions. However, the loss of conventional meta-atoms usually limits the performance potential of metasurfaces. In this study, we propose a class of metasurfaces based on discretized meta-atoms able to mitigate the radiative and intrinsic losses. By discretizing meta-atoms, we reduce the loss of metal metasurfaces to levels comparable to dielectric metasurfaces in the short-wavelength infrared region at the surface lattice resonance mode. Furthermore, we propose a coupling model to explain the observed reduction in loss in full agreement with the results obtained from finite-element method. We also reproduce this phenomenon using dielectric metasurface at electric and magnetic resonances in the visible region. Our finding offers valuable insights for the design and application of metasurfaces, while also providing theoretical implications for other resonance fields beyond metasurfaces.