title: Visible-Frequency Metasurface for Structuring and Spatially Multiplexing Optical Vortices.
abstract: A multifocus optical vortex metalens, with enhanced signal-to-noise ratio, is presented, which focuses three longitudinal vortices with distinct topological charges at different focal planes. The design largely extends the flexibility of tuning the number of vortices and their focal positions for circularly polarized light in a compact device, which provides the convenience for the nanomanipulation of optical vortices.
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.
authors.forename: M Q
authors.initials: MQ
authors.lastname: Mehmood
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.|Graduate School for Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore, 117456, Singapore.
authors.forename: Shengtao
authors.initials: S
authors.lastname: Mei
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.
authors.forename: Sajid
authors.initials: S
authors.lastname: Hussain
authors.affiliation: Institute of Materials Research and Engineering Agency for Science Technology and Research (A*STAR), Innovis, #08-03, 2 Fusionopolis Way, Singapore, 138634.
authors.forename: Kun
authors.initials: K
authors.lastname: Huang
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.
authors.forename: S Y
authors.initials: SY
authors.lastname: Siew
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.
authors.forename: Tianhang
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.|College of Physics and Electronic Engineering, Hengyang Normal University, Hengyang, 421002, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Ling
authors.affiliation: Institute of Materials Research and Engineering Agency for Science Technology and Research (A*STAR), Innovis, #08-03, 2 Fusionopolis Way, Singapore, 138634.
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Institute of Materials Research and Engineering Agency for Science Technology and Research (A*STAR), Innovis, #08-03, 2 Fusionopolis Way, Singapore, 138634.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Teng
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.
authors.forename: Aaron
authors.initials: A
authors.lastname: Danner
authors.affiliation: School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, UK.
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583.|Graduate School for Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore, 117456, Singapore.
authors.forename: Cheng-Wei
authors.initials: CW
authors.lastname: Qiu
keywords: babinet-inverted; metalens; multifocus; optical-vortex beam; topological charge