An Invisible Metallic Mesh

Abstract

We introduce a solid material that is itself invisible, possessing identical electromagnetic properties as air (i.e. not a cloak) at a desired frequency. Such a material could provide improved mechanical stability, electrical conduction and heat dissipation to a system, without disturbing incident electromagnetic radiation. One immediate application would be towards perfect antenna radomes. Unlike cloaks, such a transparent and self-invisible material has yet to be demonstrated. Previous research has shown that a single sphere or cylinder coated with plasmonic or dielectric layers can have a dark-state with considerably suppressed scattering cross-section, due to the destructive interference between two resonances in one of its scattering channels. Nevertheless, a massive collection of these objects will have an accumulated and detectable disturbance to the original field distribution. Here we overcome this bottleneck by lining up the dark-state frequencies in different channels. Specifically, we derive analytically, verify numerically and demonstrate experimentally that deliberately designed corrugated metallic wires can have record-low scattering amplitudes, achieved by aligning the nodal frequencies of the first two scattering channels. This enables an arbitrary assembly of these wires to be omnidirectionally invisible and the effective constitutive parameters nearly identical to air. Measured transmission spectra at microwave frequencies reveal indistinguishable results for all the arrangements of the 3D-printed samples studied.

arXiv comment11 pages, 3 figures

References in corpus (6)

• A Perfect Metamaterial Absorber
• Determination of Effective Permittivity and Permeability of Metamaterials from Reflection and Transmission Coefficients
• Achieving transparency with plasmonic coatings
• High-efficiency light-wave control with all-dielectric optical Huygens' metasurfaces
• Terahertz surface plasmon polariton propagation and focusing on periodically corrugated metal wires
• Electromagnetic cloaking of cylindrical objects by multilayer or uniform dielectric claddings

Cited by in corpus (6)

• Experimental discovery of nodal chains
• Invisibility on demand based on a generalized Hilbert transform
• All-dielectric self-cloaked structures
• Generalized Huygens' condition as the fulcrum of planar nonlocal omnidirectional transparency: from meta-atoms to metasurfaces
• Optical Neutrality: Invisibility without Cloaking
• Unraveling the temperature dynamics and hot electron generation in tunable gap-plasmon metasurface absorbers