Open AccessPhase-engineered metalenses to generate converging and non-diffractive vortex beam carrying orbital angular momentum in microwave region
Author(s) -
Kuang Zhang,
Ye Yuan,
Dawei Zhang,
Xumin Ding,
Badreddine Ratni,
Shah Nawaz Burokur,
Manjun Lu,
Kun Tang,
Qun Wu
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.001351
Subject(s) - optics , axicon , optical vortex , physics , angular momentum , bessel beam , beam (structure) , superposition principle , microwave , phase (matter) , lens (geology) , light beam , vortex , laser , quantum mechanics , laser beams , thermodynamics
In this paper, ultra-thin metalenses are proposed to generate converging and non-diffractive vortex beam carrying orbital angular momentum (OAM) in microwave region. Phase changes are introduced to the transmission cross-polarized wave by tailoring spatial orientation of Pancharatnam-Berry phase unit cell. Based on the superposition of phase profile of spiral phase plate and that of a converging lens or an axicon, vortex beam carrying OAM mode generated by the metalens can also exhibit characteristics of a focusing beam or a Bessel beam. Measured field intensities and phase distributions at microwave frequencies verify the theoretical design procedure. The proposed method provides an efficient approach to control the radius of vortex beam carrying OAM mode in microwave wireless applications for medium-short range distance.