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Perfect vortex (PV) beams possess a radial intensity profile independent of their topological charges, overcoming the defects of the regular vortex beams. However, the bulky optical elements used in conventional methods for generation of PV beams limit their potential applications. Metasurfaces are ultra-thin version of metamaterials with the flexible ability of controlling electromagnetic waves, promising great potential applications in many optical fields. Here, an all-dielectric metasurface based on a geometrical phase is demonstrated, featuring broadband and high efficiency in manipulation of circularly polarized light. We numerically simulate the performance of the unit-cell and metasurface for generating PV beams carrying integer and fractional topological charges. We hope the designed metasurface will provide an ultra-compact way for generation of high-quality PV beams. [ABSTRACT FROM AUTHOR]

Figures 4(d)-4(f) show the simulated intensity profile of the elliptical PV beams at the focal plane ( I z i = 14 HT ht m) with I l i = 1, 2, and 3. Publisher's Note: "Generation of integer and fractional perfect vortex beams using all-dielectric geometrical phase metasurfaces" [Appl. Phys. Also on page 4, the last paragraph, the first sentence has been corrected as "To generate an elliptical PV beam, we set ellipticity I e i as 0.7 and use 830 nm incidence in the simulation. [Extracted from the article]