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Suboptimal Coding Metasurfaces for Terahertz Diffuse Scattering.

ABSTRACT: Coding metasurfaces, composed of only two types of elements arranged according to a binary code, are attracting a steadily increasing interest in many application scenarios. In this study, we apply this concept to attain diffuse scattering at THz frequencies. Building up on previously derived theoretical results, we carry out a suboptimal metasurface design based on a simple, deterministic and computationally inexpensive algorithm that can be applied to arbitrarily large structures. For experimental validation, we fabricate and characterize three prototypes working at 1?THz, which, in accordance with numerical predictions, exhibit significant reductions of the radar cross-section, with reasonably good frequency and angular stability. Besides the radar-signature control, our results may also find potentially interesting applications to diffusive imaging, computational imaging, and (scaled to optical wavelengths) photovoltaics.

SUBMITTER: Moccia M

PROVIDER: S-EPMC6085296 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Suboptimal Coding Metasurfaces for Terahertz Diffuse Scattering.

Moccia Massimo M Koral Can C Papari Gian Paolo GP Liu Shuo S Zhang Lei L Wu Rui Yuan RY Castaldi Giuseppe G Cui Tie Jun TJ Galdi Vincenzo V Andreone Antonello A

Scientific reports 20180809 1

Coding metasurfaces, composed of only two types of elements arranged according to a binary code, are attracting a steadily increasing interest in many application scenarios. In this study, we apply this concept to attain diffuse scattering at THz frequencies. Building up on previously derived theoretical results, we carry out a suboptimal metasurface design based on a simple, deterministic and computationally inexpensive algorithm that can be applied to arbitrarily large structures. For experime ...[more]

PMID: 30093621

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