Arbitrary polarization conversion for pure vortex generation with a single metasurface
arXiv:2006.10402 · doi:10.1515/nanoph-2020-0332
Abstract
The purity of an optical vortex beam depends on the spread of its energy among different azimuthal and radial modes. The smaller is this spread, the higher is the vortex purity and the more efficient are its creation and detection. There are several methods to generate vortex beams with well-defined orbital angular momentum but only few exist allowing to select a pure radial mode. These typically consist of many optical elements with rather complex arrangements, including active cavity resonators. Here we show that it is possible to generate pure vortex beams using a single metasurface plate in combination with a polarizer. We generalize an existing theory of independent phase and amplitude control with birefringent nanopillars considering arbitrary input polarization states. The high purity, sizeable creation efficiency and impassable compactness make the presented approach a powerful complex amplitude modulation tool for pure vortex generation, even in the case of large topological charges.
References in corpus (7)
- Entanglement of Orbital Angular Momentum States of Photons
- Dielectric Metasurfaces for Complete Control of Phase and Polarization with Subwavelength Spatial Resolution and High Transmission
- Quantum information transfer from spin to orbital angular momentum of photons
- Light-induced spiral mass transport in azo-polymer films under vortex-beam illumination
- Spin-to-orbital angular momentum conversion in dielectric metasurfaces
- Beat the Rayleigh limit: OAM based super-resolution diffraction tomography
- The role of beam waist in Laguerre-Gauss expansion of vortex beam