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Related papers: Do Cloaked Objects Really Scatter Less?

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A new type of cloak is discussed: one that gives all cloaked objects the appearance of a flat conducting sheet. It has the advantage that none of the parameters of the cloak is singular and can in fact be made isotropic. It makes broadband…

Optics · Physics 2009-11-13 Jensen Li , J. B. Pendry

We develop and apply an optimization method to design invisibility cloaks. Our method is based on minimizing the forward scattering amplitude of the cloaked object, which by the optical theorem, is equivalent to the total cross section. The…

Optics · Physics 2021-03-09 Brian Slovick , Josh Hellhake

Carpet or ground-plane invisibility cloaks hide an object in reflection and inhibit transmission by construction. This concept has significantly reduced the otherwise demanding material requirements and has hence enabled various…

Optics · Physics 2015-06-12 Jad C. Halimeh , Martin Wegener

An elliptical invisible cloak is proposed using a coordinate transformation in the elliptical-cylindrical coordinate system, which crushes the cloaked object to a line segment instead of a point. The elliptical cloak is reduced to a…

Recent research on the development of a thermal cloak has concentrated on engineering an inhomogeneous thermal conductivity and homogeneous volumetric heat capacity. While the perfect cloak of inhomogeneous $\kappa$ and $\rho c_p$ is known…

Materials Science · Physics 2014-11-17 Sophia R. Sklan , Xue Bai , Baowen Li , Xiang Zhang

New connections between static elastic cloaking, low frequency elastic wave scattering and neutral inclusions are established in the context of two dimensional elasticity. A cylindrical core surrounded by a cylindrical shell is embedded in…

Classical Physics · Physics 2021-03-17 Andrew N. Norris , William J. Parnell

We show that it is possible to design an invisible wavelength-sized metal-dielectric metamaterial object without evoking cloaking. Our approach is an extension of the neutral inclusion concept by Zhou and Hu [Phys.Rev.E 74, 026607 (2006)]…

Optics · Physics 2017-04-05 Reed Hodges , Cleon Dean , Maxim Durach

We present a general framework for the computation of structure-agnostic bounds on the performance of passive cloaks over a nonzero bandwidth. We apply this framework in 2D to the canonical scenario of cloaking a circular object. We find…

Recently, it was shown that an infinite perfectly conducting (PEC) cylinder can be nearly perfectly cloaked from normally incident electromagnetic waves using a single-layer homogeneous dielectric cladding. Here we study the electromagnetic…

Mathematical Physics · Physics 2012-11-26 Constantinos A. Valagiannopoulos , Pekka Alitalo , Sergei A. Tretyakov

Invisibility cloaks, a subject that usually occurs in science fiction and myths, have attracted wide interest recently because of their possible realization. The biggest challenge to true invisibility is known to be the cloaking of a…

Optics · Physics 2013-05-29 Baile Zhang , Yuan Luo , Xiaogang Liu , George Barbastathis

Ray-tracing exercise and full-wave analysis were performed to validate the performance of a new type of cloak composed of isotropic metamaterials. It is shown that objects inside the folded region of this cloak appear invisible to the…

Optics · Physics 2009-08-25 Yu Luo , Jingjing Zhang , Hongsheng Chen , Bae-Ian Wu , Lixin Ran , Jin Au Kong

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

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

It was recently shown [Halimeh et al. arXiv:1510.06144 (to appear in Phys. Rev. A)] that as a result of the Doppler effect, inherently dispersive single-frequency ideal free-space invisibility cloaks in relative motion to an observer can…

Optics · Physics 2016-04-04 Jad C. Halimeh , Robert T. Thompson

We develop a very general theory on the regularized approximate invisibility cloaking for the wave scattering governed by the Helmholtz equation in any space dimensions via the approach of transformation optics.

Analysis of PDEs · Mathematics 2015-03-04 Jingzhi Li , Hongyu Liu , Luca Rondi , Gunther Uhlmann

Recent research in light scattering has prompted a re-evaluation of complex quantities, particularly in the context of complex frequency signals, which exhibit exponential growth or decay unlike traditional harmonic signals. We introduce a…

Classical Physics · Physics 2024-08-20 Deepanshu Trivedi , Arjuna Madanayake , Alex Krasnok

Based on a simple model of ground-plane cloaking, we argue that the diffculty of cloaking is fundamentally limited by delay-loss and delaylbandwidth/size limitations that worsen as the size of the object to be cloaked increases relative to…

Optics · Physics 2015-03-13 Hila Hashemi , Baile Zhang , J. D. Joannopoulos , Steven G. Johnson

We consider a polyhedron with zero classical resistance, i.e., a polyhedron invisible to an observer viewing only the paths of geometrical optics rays. The corresponding problem of scattering of plane waves by the polyhedron is studied. The…

Mathematical Physics · Physics 2012-04-19 E. Lakshtanov , B. D. Sleeman , B. Vainberg

The cloaking efficiency of a finite-size cylindrical transmission-line cloak operating in the X-band is verified with bistatic free space measurements. The cloak is designed and optimized with numerical full-wave simulations. The reduction…

Subwavelength structures demonstrate many unusual optical properties which can be employed for engineering functional metadevices, as well as scattering of light and invisibility cloaking. Here we demonstrate that the suppression of light…