Fig. 1
From: Multiplexing near- and far-field functionalities with high-efficiency bi-channel metasurfaces
Working principle of the bi-channel meta-surface. Schematics of a a FF bi-functional meta-device and b a NF bi-functional meta-device realized previously, and schematics of c the bi-channel meta-device proposed in this article which exhibit distinct pre-designed wave-control functionalities in NF and FF channels, respectively, under excitations of circularly polarized light with opposite helicities. The constitutional meta-atoms are in metal/insulator/metal configuration with top metallic resonators possessing tailored anisotropy and being rotated by an angle \(\xi\) with respect to the laboratory frame (inset at the right-hand side)