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Related papers: Do Cloaked Objects Really Scatter Less?

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It is shown how a recently proposed method of cloaking is effective over a broad range of frequencies. The method is based on three or more active devices. The devices, while not radiating significantly, create a ``quiet zone'' between the…

Mathematical Physics · Physics 2015-06-03 Fernando Guevara Vasquez , Graeme W. Milton , Daniel Onofrei

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

We show that cloaking of isolated objects is subject to a diameter-bandwidth product limitation: as the size of the object increases, the bandwidth of good (small cross-section) cloaking decreases inversely with the diameter, as a…

The regularized near-cloak via the transformation optics approach in the time-harmonic electromagnetic scattering is considered. This work extends the existing studies mainly in two aspects. First, it presents a near-cloak construction by…

Analysis of PDEs · Mathematics 2013-05-10 Gang Bao , Hongyu Liu , Jun Zou

Transformation-based cylindrical cloaks and concentrators are illuminated with non-monochromatic waves and unusual effects are observed with interesting potential applications. The transient responses of the devices are studied numerically…

Classical Physics · Physics 2010-01-28 Christos Argyropoulos , Efthymios Kallos , Yang Hao

Here we present the results of full experimental characterization of broadband cloaking of a finite-sized metallic cylinder at X-band. The cloaking effect is characterized by measuring the bistatic scattering patterns of uncloaked and…

We consider cloaking by a coated cylindrical system using plasmonic resonance, and extend previous quasistatic treatments to include the effect of finite wavelength. We show that a probe cylinder can still be cloaked at finite wavelengths,…

Optics · Physics 2009-11-13 N-A P Nicorovici , R C McPhedran , S Enoch , G Tayeb

Invisibility or cloaking has captured human's imagination for many years. With the recent advancement of metamaterials, several theoretical proposals show cloaking of objects is possible, however, so far there is a lack of an experimental…

Optics · Physics 2015-03-05 Jason Valentine , Jensen Li , Thomas Zentgraf , Guy Bartal , Xiang Zhang

We cloak a region from a known incident wave by surrounding the region with three or more devices that cancel out the field in the cloaked region without significantly radiating waves. Since very little waves reach scatterers within the…

Mathematical Physics · Physics 2015-06-03 Fernando Guevara Vasquez , Graeme W. Milton , Daniel Onofrei

The scattering cancellation technique is a powerful tool to reduce the scattered field from electrically small objects in a specific frequency window. The technique relies on covering the object of interest with a shell that scatters light…

We investigate the scattering of 2D cylindrical invisibility cloaks with simplified constitutive parameters with the assistance of scattering coefficients. We show that the scattering of the cloaks originates not only from the boundary…

Optics · Physics 2011-03-14 Liang Peng , Lixin Ran , N. Asger Mortensen

The scattering cancellation technique (SCT) has proved to be an effective way to render static objects invisible to electromagnetic and acoustic waves. However, rotating cylindrical or spherical objects possess additional peculiar…

Classical Physics · Physics 2020-05-27 Mohamed Farhat , Sebastien Guenneau , Andrea Alu , Ying Wu

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

The intriguing concept of "anti-cloaking" has been recently introduced within the framework of transformation optics (TO), first as a "countermeasure" to invisibility-cloaking (i.e., to restore the scattering response of a cloaked target),…

In this work we theoretically propose scattering cancellation-based cloaks for heat waves that obey the Maxwell-Cattaneo equation. The proposed cloaks possess carefully tailored diffusivity to cancel the dipole scattering from the object…

Optics · Physics 2020-04-06 M. Farhat , S. Guenneau , P. -Y. Chen , A. Alu , K. N. Salama

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

The cloaking performance of two microwave cloaks, both based on the recently proposed transmission-line approach, are studied using commercial full-wave simulation software. The cloaks are shown to be able to reduce the total scattering…

Optics · Physics 2009-04-21 Pekka Alitalo , Olli Luukkonen , Juan Mosig , Sergei Tretyakov

In this paper, we present the design of cylindrical and spherical electromagnetic cloaks working at visible frequencies. The cloak design is based on the employment of layered structures consisting of alternating plasmonic and non-plasmonic…

Optics · Physics 2008-08-01 Filiberto Bilotti , Simone Tricarico , Lucio Vegni

A new type of simplified cloaks with matched exterior boundaries is proposed. The cloak uses non-magnetic material for the TM polarization and can function with a relatively thin thickness. It is shown that the $zero^{th}$ order scattering…

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

The prospect of rendering objects invisible has intrigued researchers for centuries. Transformation optics based invisibility cloak design is now bringing this goal from science fictions to reality and has already been demonstrated…

Optics · Physics 2011-04-22 Jingjing Zhang , Liu Liu , Yu Luo , Shuang Zhang , Niels Asger Mortensen