High-purity orbital angular momentum vortex beam generator using an amplitude-and-phase metasurface

In this Letter, we propose an approach to generate high-purity orbital angular momentum (OAM) vortex waves using an amplitude-and-phase metasurface (APM). By varying the square split ring opening and orientation angles, the cross-polarized reflection response of the proposed structure can yield full...

Full description

Saved in:
Bibliographic Details
Published in:Optics letters 2021-12, Vol.46 (23), p.5790-5793
Main Authors: Zheng, Sen, Hao, Honggang, Tang, Yihao, Ran, Xuehong
Format: Article
Language:English
Subjects:
Amplitudes
Angle of reflection
Angular momentum
Chebyshev approximation
Electron beams
Metasurfaces
Purity
Ring opening
Vortices
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this Letter, we propose an approach to generate high-purity orbital angular momentum (OAM) vortex waves using an amplitude-and-phase metasurface (APM). By varying the square split ring opening and orientation angles, the cross-polarized reflection response of the proposed structure can yield full phase and amplitude coverage. Based on the traditional phase-only metasurface (POM), the Chebyshev synthesis method (CSM) is applied to array the metasurface amplitude distribution. Metasurfaces with modes l of 1, 2, 3, and 4 are designed. Compared with the POM, the APM can effectively improve the vortex beam quality and OAM mode purity. The measured results agree well with full-wave simulations. The presented method provides a new, to the best of our knowledge, way to design high-purity OAM generators based on metasurfaces.
ISSN:0146-9592
1539-4794
DOI:10.1364/OL.441426