Trichannel Spin-Selective Metalenses

Metalenses have the potential to revolutionize opticaldevicesinto the next generation of consumer devices. Through new inventivestrategies, metalenses with advanced functionalities have been releasedto integrate multiple responses into a single flat device. Here, wedesign metalenses that are sensitive to the incident spin angularmomentum to provide three distinct modes based on the handedness ofthe incident and transmitted light. Propagation phase is employedto encode a hyperbolic lens phase to the metalens, while geometricphase is exploited for additional spin-selective properties. We experimentallydemonstrate two different metalenses: the co-polarized channels functionas a standard metalens, while the cross-polarized channels (1) deflectand (2) introduce orbital angular momentum to the transmitted light.We experimentally characterize the metalenses and prove their usefor spin-selective imaging of visible light. We envision that suchtrichannel metalenses could be employed in chiral bioimaging, opticalcomputing, and computer vision.