Perfect-Lens Theory Enables Metasurface Reflectors for Subwavelength Focusing

Taghvaee, Hamidreza; Liu, Fu; Díaz-Rubio, Ana; Tretyakov, Sergei

Abstract

Breaking the so-called diffraction limit on the resolution of optical devices and achieving subwavelength focusing requires tailoring the evanescent spectrum of wave fields. There are several possible approaches, all of which have limitations, such as the generation of strong additional scattering, limited focusing power, issues at the implementation step, and the need for a drain at the focal point. This paper presents a feasible strategy based on the concepts of the perfect lens and power flow-conformal metasurfaces. Desired fields for subwavelength focusing are integrated using double-negative media and then the surface profile of a focusing reflector is designed to be tangential to the desired power flow, so that the metasurface can be modeled as a local impedance boundary, and can be easily implemented using passive and lossless elements. Full-wave simulations demonstrate that an example reactive metasurface is able to break the diffraction limit and provide near-field focusing with subwavelength hotspot size. We expect that the outcome will find applications in antennas, beam-shaping devices, nonradiative wireless power transfer systems, microscopy, and lithography.

Citation

Taghvaee, H., Liu, F., Díaz-Rubio, A., & Tretyakov, S. (2023). Perfect-Lens Theory Enables Metasurface Reflectors for Subwavelength Focusing. Physical Review Applied, 19(1), Article 014004. https://doi.org/10.1103/PhysRevApplied.19.014004

• Journal Article Type: Article
• Acceptance Date: Nov 7, 2022
• Online Publication Date: Jan 3, 2023
• Publication Date: Jan 3, 2023
• Deposit Date: Jan 24, 2023
• Publicly Available Date: Jan 27, 2023
• Journal: Physical Review Applied
• Electronic ISSN: 2331-7019
• Publisher: American Physical Society (APS)
• Peer Reviewed: Peer Reviewed
• Volume: 19
• Issue: 1
• Article Number: 014004
• DOI: https://doi.org/10.1103/PhysRevApplied.19.014004
• Keywords: General Physics and Astronomy
• Public URL: https://nottingham-repository.worktribe.com/output/15718420
• Publisher URL: https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.19.014004