Plasmonic fork-shaped hologram for vortex-beam generation and separation

We introduce a multifunctional compact device that integrates a polarization beam splitter and an orbital angular momentum generator based on a plasmonic nano-aperture assisted detour phase meta-hologram. The proposed metasurface, which combines a phase singularity characterized fork hologram and polarization featured Λ-shaped antenna, achieves vortex generation and spin-based vortex splitting in transmission mode. Experimental demonstrations are launched under a linearly polarized incident beam, with polarization tomography as the analysis method. We expect this work to have applications in chip-level beam shaping and high-capacity communication.