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Related papers: Active Exterior Cloaking

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We design a device that generates fields canceling out a known probing field inside a region to be cloaked while generating very small fields far away from the device. The fields we consider satisfy the Laplace equation, but the approach…

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

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

We design sources for the two-dimensional Helmholtz equation that can cloak an object by cancelling out the incident field in a region, without the sources completely surrounding the object to hide. As in previous work for real positive…

Analysis of PDEs · Mathematics 2022-03-07 Maxence Cassier , Trent DeGiovanni , Sébastien Guenneau , Fernando Guevara Vasquez

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

In this paper, we study approximate cloaking of active devices for the Helmholtz equation in the whole space of dimension 2 or 3 using the scheme introduced by Kohn, Shen, Vogelius, and Weinstein in \cite{KohnShenVogeliusWeinstein}. More…

Mathematical Physics · Physics 2011-09-30 Hoai-Minh Nguyen

Following the ideas proposed in \cite{OMV1} and \cite{OMV2} on active exterior cloaking, we present here a systematic integral equation method to generate suitable quasistatic fields for cloaking, illusions and energy focusing (with given…

Analysis of PDEs · Mathematics 2012-05-08 Daniel Onofrei

Recently, it was demonstrated that active sources can be used to cloak any objects that lie outside the cloaking devices [Phys. Rev. Lett. \textbf{103}, 073901 (2009)]. Here, we propose that active sources can create illusion effects, so…

Optics · Physics 2013-07-04 H. H. Zheng , J. J. Xiao , Y. Lai , C. T. Chan

The aim of this paper is to extend the method of improving cloaking structures in the conductivity to scattering problems. We construct very effective near-cloaking structures for the scattering problem at a fixed frequency. These new…

Analysis of PDEs · Mathematics 2015-05-30 Habib Ammari , Hyeonbae Kang , Hyundae Lee , Mikyoung Lim

Electromagnetic cloaking refers to the ability to prevent an object from scattering an incident electromagnetic field. This has been accomplished in recent works by routing the incident field around the object or by changing the scattering…

Classical Physics · Physics 2012-06-21 Michael Selvanayagam , George V. Eleftheriades

Transformation optics constructions have allowed the design of cloaking devices that steer electromagnetic, acoustic and quantum waves around a region without penetrating it, so that this region is hidden from external observations. The…

Analysis of PDEs · Mathematics 2011-01-04 Matti Lassas , Ting Zhou

We present an active cloaking method for the parabolic heat (and mass or light diffusion) equation that can hide both objects and sources. By active we mean that it relies on designing monopole and dipole heat source distributions on the…

Analysis of PDEs · Mathematics 2021-06-09 Maxence Cassier , Trent DeGiovanni , Sébastien Guenneau , Fernando Guevara Vasquez

In this paper, we present various schemes of cloaking an arbitrary objects via anomalous localized resonance and provide their analysis in two and three dimensions. This is a way to cloak an object using negative index materials in which…

Mathematical Physics · Physics 2016-07-25 Hoai-Minh Nguyen

We describe an effective active cloaking strategy for the scalar Helmholtz equation in three dimensions where multipole active sources are located at the vertices of the Platonic solids. A "silent zone" is created interior to the imaginary…

Classical Physics · Physics 2021-09-30 Cheuk-Him Yeung , Tom Shearer , William J Parnell

Rendering objects invisible to impinging acoustic waves (cloaking) and creating acoustic illusions (holography) has been attempted using active and passive approaches. While passive methods are applicable only to narrow frequency bands,…

An active elastodynamic cloak destructively interferes with an incident time harmonic in-plane (coupled compressional/shear) elastic wave to produce zero total elastic field over a finite spatial region. A method is described which…

Mathematical Physics · Physics 2013-10-11 Andrew N. Norris , Feruza A. Amirkulova , William J. Parnell

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

Based on the concept of complementary media, we propose an invisibility cloak operating at a finite frequency that can cloak an object with a pre-specified shape and size within a certain distance outside the shell. The cloak comprises of a…

Optics · Physics 2009-11-13 Yun Lai , Huanyang Chen , Zhao-Qing Zhang , C. T. Chan

We demonstrate three simple cloaking devices that can hide very large spatial objects over the entire visible spectrum using only passive, off-the-shelf optics. The cloaked region for all of the devices exceeds 10^6 mm3 with the largest…

Optics · Physics 2015-06-16 John C. Howell , J. Benjamin Howell

Space folding techniques based on non-monotonic transforms lead to a new class of cylindrical isotropic acoustic cloaks with a constant negative density and a spatially varying negative bulk modulus. We consider an external cloak consisting…

Computational Physics · Physics 2021-01-01 Sebastien Guenneau , Bruno Lombard , Cedric Bellis

Cloaking using complementary media was suggested by Lai et al. in [8]. The study of this problem faces two difficulties. Firstly, this problem is unstable since the equations describing the phenomenon have sign changing coefficients, hence…

Analysis of PDEs · Mathematics 2015-07-08 Hoai-Minh Nguyen
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