Abstract
We theoretically study a tunable reflective focusing lens, based on graphene metasurface, which consists of rectangle aperture array. Dynamic control of either the focal intensity or focal length for terahertz circular polarized waves can be achieved by uniformly tuning the graphene Fermi energy. We demonstrate the graphene apertures with the same geometry; however, spatially varying orientations can only control the focal intensity. To change the focal length, the spatially varying aperture lengths are also required. A comparative study between the metalenses, which generate only geometric or both gradient and geometric phase changes, has shown that the apertures' spatially varying length distribution is the key factor for determining the modulation level, rather than the focal length's modulation range. This kind of metalens provides tunable, high-efficiency, broadband, and wide-angle off-axis focusing, thereby offering great application potential in lightweight and integrated terahertz devices.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.