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Related papers: The Anti-Cloak

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An active interior cloak is composed of a conformal array of radiating sources surrounding a target object. With proper configuration, this array radiates a field discontinuity which cancels out any scattering which occurs when the object…

Applied Physics · Physics 2024-09-26 Paris Ang , George V. Eleftheriades

Non-Euclidean geometry combined with transformation optics has recently led to the proposal of an invisibility cloak that avoids optical singularities and therefore can work, in principle, in a broad band of the spectrum [U. Leonhardt and…

Optics · Physics 2014-06-16 Tomas Tyc , Huanyang Chen , Che Ting Chan , Ulf Leonhardt

We consider an ideal invisibility cloak which is illuminated by monochromatic light and which moves in vacuum at constant relativistic velocity with respect to the common inertial frame of light source and observer. We show that, in…

Optics · Physics 2016-02-03 Jad C. Halimeh , Robert T. Thompson , Martin Wegener

This paper proposes a radial dependent dispersive finite-difference time-domain method for the modelling of electromagnetic cloaking structures. The permittivity and permeability of the cloak are mapped to the Drude dispersion model and…

Classical Physics · Physics 2009-11-13 Yan Zhao , Christos Argyropoulos , Yang Hao

We experimentally demonstrated an alternative approach of invisibility cloaking that can combine technical advantages of all current major cloaking strategies in a unified manner and thus can solve bottlenecks of individual strategies. A…

If an object is very small in size compared with the wavelength of light, it does not scatter light efficiently. It is hence difficult to detect a very small object with light. We show using analytic theory as well as full wave numerical…

Optics · Physics 2015-10-20 Meng Xiao , Xueqin Huang , H. Liu , C. T. Chan

The onset of transformation optics has opened avenues for designing of a plenitude of applications related to propagation of electromagnetic waves in anisotropic media. In this paper, an algorithm is proposed using a coordinate…

Optics · Physics 2015-11-30 H. H. Sidhwa , R. P. Aiyar , S. V. Kulkarni

Coordinate-transformation approaches to invisibility cloaking rely on the design of an anisotropic, spatially inhomogeneous "transformation medium" capable of suitably re-routing the energy flux around the region to conceal without causing…

Optics · Physics 2015-05-13 Giuseppe Castaldi , Ilaria Gallina , Vincenzo Galdi

The electromagnetic implementation of cloaking, the hiding of objects from sight by diverting and reassembling illuminating electromagnetic fields has now been with us ten years, while the notion of hiding events is now five. Both schemes…

By investigating wave properties at cloak boundaries, invisibility cloaks with arbitrary shape constructed by general coordinate transformations are confirmed to be perfectly invisible to the external incident wave. The differences between…

Optics · Physics 2009-11-13 Wei Yan , Min Yan , Zhichao Ruan , Min Qiu

Combining the tools for transforming space-time developed for General Relativity with the capabilities of artificially structured metamaterials, an entirely new means of controlling electromagnetic fields has emerged. Here, we utilize a…

It was proposed that perfect invisibility cloaks can be constructed for hiding objects from electromagnetic illumination (Pendry et al., Science 312, p. 1780). The cylindrical cloaks experimentally demonstrated (Schurig et al., Science 314,…

Optics · Physics 2008-02-25 Min Yan , Zhichao Ruan , Min Qiu

The experimental realization of cloaks for electromagnetic fields has been possible only in reduced schemes because of extreme material conditions required in exact cloaks. Here we analytically demonstrate that a simple arrangement of two…

Superconductivity · Physics 2011-12-14 Carles Navau , Jordi Prat-Camps , Alvaro Sanchez

There has recently been considerable interest in the possibility, both theoretical and practical, of invisibility (or "cloaking") from observation by electromagnetic (EM) waves. Here, we prove invisibility, with respect to solutions of the…

Analysis of PDEs · Mathematics 2009-11-11 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

We show that dielectric or even perfectly conducting cylinders can be cloaked by a uniform or a layered dielectric cladding, without the need of any exotic or magnetic material parameters. In particular, we start by presenting a simple…

Classical Physics · Physics 2015-06-03 Constantinos A. Valagiannopoulos , Pekka Alitalo

Two novel classes of spherical invisibility cloaks based on nonlinear transformation have been studied. The cloaking characteristics are presented by segmenting the nonlinear transformation based spherical cloak into concentric isotropic…

The possibility of making an optically large (many wavelengths in diameter) object appear invisible has been a subject of many recent studies. Exact invisibility scenarios for large (relative to the wavelength) objects involve…

Optics · Physics 2015-06-11 Yaroslav Urzhumov , David R. Smith

We extend the design of radially symmetric three-dimensional invisibility cloaks through transformation optics to cloaks with a surface of revolution. We derive the expression of the transformation matrix and show that one of its…

This paper is concerned with the invisibility cloaking in acoustic wave scattering from a new perspective. We are especially interested in achieving the invisibility cloaking by completely regular and isotropic mediums. It is shown that an…

Analysis of PDEs · Mathematics 2016-04-20 Xia Ji , Hongyu Liu

We examine several ways to manipulate the loss in electromagnetic cloaks, based on transformation electromagnetics. It is found that, by utilizing inherent electric and magnetic losses of metamaterials, perfect wave absorption can be…

Classical Physics · Physics 2015-05-13 Christos Argyropoulos , Efthymios Kallos , Yan Zhao , Yang Hao
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