Generation of terahertz vector beams using dielectric metasurfaces via spin-decoupled phase control
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[21928614 - Nanophotonics] Generation of terahertz vector beams using dielectric metasurfaces via spin-decoupled phase control.pdf
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ArticleAuthors
Xu, YuehongZhang, Huifang
Li, Quan
Zhang, Xueqian
Xu, Quan
Zhang, Wentao
Hu, Cong
Zhang, Xixiang
Han, Jiaguang
Zhang, Weili
KAUST Department
Material Science and Engineering ProgramPhysical Science and Engineering (PSE) Division
KAUST Grant Number
URF-2950-CRG5CRF-2016-2950-RG5
CRF-2017-3427-CRG6)
Date
2020-06-30Online Publication Date
2020-06-30Print Publication Date
2020-06-25Submitted Date
2020-02-13Permanent link to this record
http://hdl.handle.net/10754/665358Metadata
Show full item recordAbstract
Cylindrical vector beams (CVBs), being a special kind of beams with spatially variant states of polarizations, are promising in photonics applications, including high-resolution imaging, plasmon excitation, optical trapping, and laser machining. Recently, generating CVBs using metasurfaces has drawn enormous interest owing to their highly designable, multifunctional, and integratable features. However, related studies remain unexplored in the terahertz regime. Here, a generic method for efficiently generating terahertz CVBs carrying orbital angular momentums (OAMs) is proposed and experimentally demonstrated using transmission-type spatial-variant dielectric metasurfaces, which is realized by designing the interference between the two circularly polarized transmission components. This method is based on spin-decoupled phase control allowed by simultaneously manipulating the dynamic phase and geometric phase of each structure, endowing more degree of freedom in designing the vector beams. Two types of metasurfaces which respectively generate polarization-dependent terahertz vector vortex beams (VVBs) and vector Bessel beams (VBBs) are experimentally characterized. The proposed method opens a new window to generate versatile vector beams, providing new capabilities in developing novel, compact, and high-performance devices applicable to broad electromagnetic spectral regimes.Citation
Xu, Y., Zhang, H., Li, Q., Zhang, X., Xu, Q., Zhang, W., … Zhang, W. (2020). Generation of terahertz vector beams using dielectric metasurfaces via spin-decoupled phase control. Nanophotonics, 9(10), 3393–3402. doi:10.1515/nanoph-2020-0112Sponsors
This research was funded by the National Natural Science Foundation of China (Grant Nos. 61605143, 61735012, 11974259, 61705167, 61875150, and 61420106006); Tianjin Municipal Fund for Distinguished Young Scholars (grant No. 18JCJQJC45600); Scientific Research Project of Tianjin Education Commission (Grant No. JWK1608); Start-up project of scientific research of Tianjin University of Technology and Education (Grant No. KYQD1718); Guangxi Key Laboratory of Automatic Detecting Technology and Instruments (YQ17203, YQ18205); King Abdullah University of Science and Technology, Office of Sponsored Research (Grand Nos. URF-2950-CRG5, CRF-2016-2950-RG5, and CRF-2017-3427-CRG6).Publisher
Walter de Gruyter GmbHJournal
NanophotonicsScopus Count
Except where otherwise noted, this item's license is described as This work is licensed under the Creative Commons Attribution 4.0 International License.
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