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arXiv · 1203.5831

Isotropic-medium three-dimensional cloaks for acoustic and electromagnetic waves

Yaroslav Urzhumov·Nathan Landy·David R. Smith
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Abstract

We propose a generalization of the two-dimensional eikonal-limit cloak derived from a conformal transformation to three dimensions. The proposed cloak is a spherical shell composed of only isotropic media; it operates in the transmission mode and requires no mirror or ground plane. Unlike the well-known omnidirectional spherical cloaks, it may reduce visibility of an arbitrary object only for a very limited range of observation angles. In the short-wavelength limit, this cloaking structure restores not only the trajectories of incident rays, but also their phase, which is a necessary ingredient to complete invisibility. Both scalar-wave (acoustic) and transverse vector-wave (electromagnetic) versions are presented.

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Yaroslav Urzhumov, Nathan Landy, David R. Smith. 2012-03-26. Isotropic-medium three-dimensional cloaks for acoustic and electromagnetic waves. https://doi.org/10.1063/1.3691242

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