High-Performance Broadband Circularly Polarized Beam Deflector by Mirror Effect of Multinanorod Metasurfaces

Manipulation of light phase and amplitude by plasmonic metasurfaces has immensely promising applications in optical imaging, information processing, communications, and quantum optics. However, the controllability of efficiency and bandwidth is relatively low for the single-layer metasurfaces. Here, a high efficiency and broadband circularly polarized (CP) beam deflector based on multirod single-layer metasurfaces is presented. Each unit can be regarded as an imperfect polarizer, and the phase and amplitude induced by the mirror effect can be easily controlled. Owing to the plasmonic hybridization, the high efficiency and broadband characteristics of the proposed metasurfaces are theoretically and experimentally demonstrated. Meanwhile, an easy way to determine the polarization degree of the incident light based on Poincare sphere is also proved by the multirod metasurfaces. Our work provides a simple alternative way to enhance the efficiency of CP anomalous light and thus has robust applications in nanophotonics and nanooptics.