Phyllotaxis-inspired nanosieves with multiplexed orbital angular momentum

Abstract Nanophotonic platforms such as metasurfaces, achieving arbitrary phase profiles within ultrathin thickness, emerge miniaturized, ultracompact and kaleidoscopic optical vortex generators. However, it is often required to segment or interleave independent sub-array metasurfaces multiplex vortices in a single nano-device, which turn affects the device’s compactness channel capacity. Here, inspired by phyllotaxis patterns pine cones sunflowers, we theoretically prove experimentally report that multiple can be produced compact nanosieve, both free space on chip, where one meta-atom may contribute many simultaneously. The time-resolved dynamics of on-chip interference wavefronts between plasmonic was revealed ultrafast photoemission electron microscopy. Our nature-inspired generator would facilitate various vortex-related applications, including structured wavefront shaping, free-space vortices, high-capacity information metaphotonics.