A kind of metasurface cylindrical vector light (CVL) generator in the visible region is proposed. This kind of CVL generator consists of nanometer holes etched on silver film, and it can change any linearly or circularly polarized light into the CVL in nanoscale. The order of the generated CVL is controlled by the rotation of the holes and its polarization state changes with the incident polarization condition. The base transformation theory guides is used to design the metasurface. The numerical simulations for the transmission of the proposed CVL generators confirm the validity of the theoretical predictions, and they also provide the available parameters for practical metasurface devices. The experimental results verify the performance of the proposed metasurface CVL generators. This kind of vector light generator has the advantages of thin and compact structure, polarization multiplexing and convenient manufacture. This work paves a new path for designing the miniature devices to generate the vector light field and it will promote the applications of polarization devices in optical integration and micro-manipulation.

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In view of wide applications of structured light fields and plasmonic vortices, we propose the concept of compound plasmonic vortex and design several structured plasmonic vortex generators. This kind of structured plasmonic vortex generators consists of multiple spiral nanoslits and they can generate two or more concentric plasmonic vortices. Different from Laguerre-Gaussian beam, the topological charge of the plasmonic vortex in different region is different. Theoretical analysis lays the basis for the design of radially structured plasmonic vortex generators and numerical simulations for several examples confirm the effectiveness of the design principle. The discussions about the interference of vortex fields definite the generation condition for the structured vortex.This work provides a design methodology for generating new vortices using spiral nanoslits and the advanced radially structured plasmonic vortices is helpful for broadening the applications of vortex fields.

Two kinds of plasmonic lenses are proposed based on phase compensation. Each kind of plasmonic lens is comprised of four sets of nanohole arrays, and two sets of face-to-face nanohole arrays are planar symmetric. The adjustment of separation and the rotation angle of holes compensates, respectively, for the phase difference of the surface plasmon polaritons reaching to the focal spot. The different design principles make the proposed plasmonic lenses show the different polarization dependence focusing. Two or four foci of the first kind of plasmonic lens and two controllable foci focusing of the second kind of plasmonic lens can be utilized as optical switch and logic judgment. Theoretic analysis, numerical calculations and experiment measurement verify the focusing performance of our proposed plasmonic lenses. The focusing functionality and versatility of our proposed structures are helpful for extending the applications of plasmonic lenses in integrated optics.

Several metasurface diffraction-free beam generators are designed by using a set of resonant V-shaped nanoholes. Cosine beams, Bessel beams and cosine Bessel beams are generated through the corresponding metasurface structures with V-shaped nanoholes arranged in different ways. Theoretical analysis provides the design mechanism for these diffraction-free beam generators, numerical simulations and experiment measurement give the powerful verification for the generation of diffraction-free beams. The proposed diffraction-free beam generators have advantages of ultra-thin thickness, compact structure, ease to manufacture and flexibility to operate. The generated diffraction-free beams show high efficiency, polarization independence and validity for any visible wavelength. The compact design is benefit to the applications of diffraction-free beams in nanometer fabrication, optical integrated imaging and optical micromanipulation.