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arXiv · 1001.3000

Power scattering and absorption mediated by cloak/anti-cloak interactions: A transformation-optics route towards invisible sensors

Giuseppe Castaldi·Ilaria Gallina·Vincenzo Galdi·Andrea Alu'·Nader Engheta
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Abstract

The suggestive idea of "cloaking" an electromagnetic sensor, i.e., strongly reducing its visibility (scattering) while maintaining its field-sensing (absorption) capabilities, has recently been proposed in the literature, based on scattering-cancellation, Fano-resonance, or transformation-optics approaches. In this paper, we explore an alternative, transformation-optics-based route, which relies on the recently-introduced concept of "anti-cloaking." More specifically, our proposed approach relies on a suitable tailoring of the competing cloaking and anti-cloaking mechanisms, interacting in a two-dimensional cylindrical scenario. Via analytical and parametric studies, we illustrate the underlying phenomenology, identify the critical design parameters, and address the relevant optimality and tradeoff issues, taking also into account the effect of material losses. Our results confirm the envisaged potentials of the proposed transformation-optics approach as an attractive alternative route to sensor cloaking.

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Giuseppe Castaldi, Ilaria Gallina, Vincenzo Galdi, Andrea Alu', Nader Engheta. 2010-01-18. Power scattering and absorption mediated by cloak/anti-cloak interactions: A transformation-optics route towards invisible sensors. https://doi.org/10.1364/josab.27.002132

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