Perfect vector vortex beams (PVVBs), which are characterized by spiral phase, donut-shaped intensity profile and inhomogeneous polarization of a light beam carrying spin angular momentum (SAM) and orbital angular momentum (OAM), have a constant bright ring radius and ring width which are unaffected by the changes of their carrying topological charge (TC), thus making them highly valuable in many optical fields. Metasurfaces, as planar optical devices composed of subwavelength nanostructures, can precisely control the phase, polarization, and amplitude of electromagnetic waves, providing a revolutionary solution for integrated vector field manipulation devices. However, existing metasurfaces still encounter significant challenges in generating high-capacity, polarization- and orbital angular momentum-independent controlled perfect vector vortex beams. In order to solve this problem, in this work a spin-multiplexing scheme based on pure geometric phase modulation on a metasurface platform is used to achieve high-capacity polarization- and OAM-independent controlled PVVBs. The metasurfaces with a combined phase profile of a spiral phase plate, an axicon, and a focusing (Fourier) lens are spatially encoded by rectangular Ge2Sb2Se4Te1 (GSST) nanopillar with various orientations on a CaF2 square substrate. When illuminated by circularly polarized light with opposite chirality, the metasurfaces can generate various perfect vector vortex beams (PVBs) with arbitrary topological charges. For linearly polarized incidence, the metasurface is employed to induce PVVBs by coherently superposing PVBs with spin-opposite OAM modes. The polarization states and polarization orders of the generated PVVBs can be flexibly customized by controlling the initial phase difference, amplitude ratio, and topological charges of the two orthogonal PVB components. Notably, through precisely designing the metasurface’s phase distribution and the propagation path of the generated beams, the space and polarization multiplexing can be realized in a compact manner of spatial PVVB arrays, significantly increasing both information channels and dimensions for the development of vortex communication capacity. With these findings, we demonstrate an innovative optical information encryption scheme by using a single metasurface to encode personalized polarization states and OAM in parallel channels embedded within multiple PVVBs. This work aims to establish an ultra-compact, robust platform for generating multi-channel high-capacity polarization- and OAM-independent controlled PVVBs in the mid-infrared range, and promote their applications in optical encryption, particle manipulation, and quantum optics.
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