All-dielectric metasurfaces capable of polarization detection and vortex beams generation

Metasurfaces are the ultrathin version of metamaterials with the flexible ability to control and identify polarization states. Here, an all-dielectric metasurface based on TiO2 is demonstrated, combining the principle of holographic imaging and using image intensity as a key parameter, vividly realizing one-to-one mapping of linear polarization states with far-field images. In addition, combining the focusing with a polarization multiplexing principle to distinguish the spin direction of circular polarization light and generate the high-purity vortex beams with energy offset, the proposed capabilities have potential applications in the fields of polarization detection, optical beam research, and communication. (c) 2023 Optica Publishing Group