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arXiv · 0905.1703

Electromagnetic interaction of arbitrary radial-dependent anisotropic spheres and improved invisibility for nonlinear-transformation-based cloaks

Cheng-Wei Qiu·Andrey Novitsky·Hua Ma·Shaobo Qu
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Abstract

An analytical method of electromagnetic wave interactions with a general radially anisotropic cloak is established. It is able to deal with arbitrary parameters ($ε_r(r)$, $μ_r(r)$, $ε_t(r)$ and $μ_t(r)$) of a radially anisotropic inhomogeneous shell. The general cloaking condition is proposed from the wave relations for the first time. We derive the parameters of a novel class of spherical nonlinear cloaks and examine its invisibility performance by the proposed method at various nonlinear situations. Spherical metamaterial cloaks with improved invisibility performance is achieved with optimal nonlinearity in transformation and core-shell ratio.

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Cheng-Wei Qiu, Andrey Novitsky, Hua Ma, Shaobo Qu. 2009-10-01. Electromagnetic interaction of arbitrary radial-dependent anisotropic spheres and improved invisibility for nonlinear-transformation-based cloaks. https://doi.org/10.1103/physreve.80.016604

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