Achieving invisibility over a finite range of frequencies

Institut Fresnel, CNRS, Aix-Marseille Université, 13013 Marseille, France.
Optics Express (Impact Factor: 3.49). 05/2008; 16(8):5656-61. DOI: 10.1364/OE.16.005656
Source: PubMed

ABSTRACT We analyze cloaking of transverse electric (TE) fields through homogenization of radially symmetric metallic structures. The two-dimensional circular cloak consists of concentric layers cut into a large number of small infinitely conducting sectors which is equivalent to a highly anisotropic permittivity. We find that a wave radiated by a magnetic line current source located a couple of wavelengths away from the cloak is almost unperturbed in magnitude but not in phase. Our structured cloak is shown to work for different wavelengths provided they are ten times larger than the outermost sectors.

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Available from: Sebastien Guenneau, Sep 01, 2015
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    • "It made the design and implementation of the experiments very complicated and expensive. Also, all the theoretical predictions and experiments reported worked only at a single frequency or in a narrow band [5] [6] [7] [8] [9] [10] [11]. However, regardless of how complicated the theory is, finally, it does not step beyond the scope of the principle of geometrical optics, or the electromagnetism theory of geometrical optics. "
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    • "Huang et al. proposed a concentric multilayered design of cylindrical electromagnetic cloaks [29]. Farhat et al. further divided these layers in infinitely conducting sectors in the context of electromagnetics [30]. A very comphensive, yet rigorous, mathematical account of the homogenization approach to cloaking can be found in a physics paper by Greenleaf et al. [12], while numerical illustrations of this theory are discussed in Farhat et al. [13]. "
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