Premium
Geometric Phase Based Circular Array for Multimode Vortex Beam Generation
Author(s) -
Li Quan,
Wu Chao,
Liu Xuan,
Zhao Song,
Zhang Zhihui,
Shang Xiaobing,
Wei Zeyong,
Li Hongqiang
Publication year - 2019
Publication title -
annalen der physik
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.009
H-Index - 68
eISSN - 1521-3889
pISSN - 0003-3804
DOI - 10.1002/andp.201900367
Subject(s) - physics , geometric phase , optics , circular polarization , rotation (mathematics) , polarization (electrochemistry) , phase (matter) , stokes parameters , optical vortex , angular momentum , microwave , circular buffer , scattering , near and far field , electromagnetic radiation , beam (structure) , classical mechanics , geometry , computer science , programming language , quantum mechanics , chemistry , mathematics , microstrip
A geometric phase model for electromagnetic radiating elements is proposed. By rotation of the radiating element, a frequency‐independent geometric phase occurs for circularly polarized components of radiation field along every direction in far field. In addition, the geometric phase is equal to the rotation angle for a circularly polarized source, which enables phase modulation ranging from 0 to 2π. In contrast, the Pancharatnam–Berry phase for circular polarization conversion components brought by optical element rotation is twice the rotation angle and is applicable only for the scattering waves propagating along the rotation axis. As a proof of principle, an antenna array is designed and fabricated in microwave regime to verify the phase modulation approach. Both the calculated and measured results verify that three different orbital angular momentum modes are generated simultaneously at 8.5 GHz and 11.5 GHz.