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arXiv · 1501.00392

Scattering Suppression from Arbitrary Objects in Spatially-Dispersive Layered Metamaterials

Abstract

Concealing objects by making them invisible to an external electromagnetic probe is coined by the term cloaking. Cloaking devices, having numerous potential applications, are still face challenges in realization, especially in the visible spectral range. In particular, inherent losses and extreme parameters of metamaterials required for the cloak implementation are the limiting factors. Here, we numerically demonstrate nearly perfect suppression of scattering from arbitrary shaped objects in spatially dispersive metamaterial acting as an alignment-free concealing cover. We consider a realization of a metamaterial as a metal-dielectric multilayer and demonstrate suppression of scattering from an arbitrary object in forward and backward directions with perfectly preserved wavefronts and less than 10% absolute intensity change, despite spatial dispersion effects present in the composite metamaterial. Beyond the usual scattering suppression applications, the proposed configuration may serve as a simple realisation of scattering-free detectors and sensors.

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Alexander S. Shalin, Pavel Ginzburg, Alexey A. Orlov, Ivan Iorsh, Pavel A. Belov, Yuri S. Kivshar, Anatoly V. Zayats. 2015-01-02. Scattering Suppression from Arbitrary Objects in Spatially-Dispersive Layered Metamaterials. https://doi.org/10.1103/physrevb.91.125426

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