Generating Focused 3D Perfect Vortex Beams By Plasmonic Metasurfaces

摘要

Perfect vortex (PV) beams possessing annular intensity profiles independentrnof topological charges promise significant advances in particle manipulation,rnfiber communication, and quantum optics. The PV beam is typically generatedrnfrom the Fourier transformation of the Bessel–Gauss beam. However,rnthe conventional method to produce PV beams requires a series of bulkyrnoptical components, which greatly increases the system complexity and alsornhinders the photonic device integration. Here, plasmonic metasurfaces madernof rectangular-hole nanoantennas as integrated beam converters are designedrnand demonstrated to generate focused 3D PV beams in a broad wavelengthrnrange, by combining the phase profiles of axicon, spiral phase plate, and Fourierrntransform lens simultaneously based on the Pancharatnam–Berry phase.rnIt is demonstrated that the PV beam structures can be adjusted by varyingrnseveral control parameters in the metasurface design. Moreover, multiple PVrnbeams with arbitrary arrangement and topological charges are also produced.rnThese results have the promising potential for enabling new types of compactrnoptical devices for tailoring complex light beams and advancing metasurfacebasedrnfunctional integrated photonic chips.