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Related papers: Active Thermal Cloaking and Mimicking

200 papers

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

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

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

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

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

All the thermal cloaks reported in the literature can be used to thermally hide an object inside the cloak. However, a common limitation of this kind of thermal cloaks is that the cloaked object cannot feel the external heat flow since it…

Materials Science · Physics 2013-12-12 Y. Gao , J. P. Huang

We propose a realization of a transformation-based acoustic temporal cloak using an active closed-loop control approach to an equivalent electromagnetic problem. Unlike the more common spatial cloaks the goal of which is hiding fixed…

Applied Physics · Physics 2023-08-02 Or Lasri , Lea Sirota

Here, we adapt the concept of transformational thermodynamics, whereby the flux of temperature is controlled via anisotropic heterogeneous diffusivity, for the diffusion and transport of mass concentration. The n-dimensional,…

Biological Physics · Physics 2013-02-01 Sebastien Guenneau , Tania Puvirajesinghe

Hiding an object in a chemical gradient requires to suppress the distortions it would naturally cause on it. To do so, we propose a strategy based on coating the object with a chemical reaction-diffusion network which can act as an active…

Chemical Physics · Physics 2020-07-01 Francesco Avanzini , Gianmaria Falasco , Massimiliano Esposito

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

We report on a new concept of cloaking objects in diffusive light regime using the paradigm of the scattering cancellation and mantle cloaking techniques. We show numerically that an object can be made completely invisible to diffusive…

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,…

The ability to control electromagnetic fields, heat currents, electric currents, and other physical phenomena by coordinate transformation methods has resulted in novel functionalities, such as cloaking, field rotations, and concentration…

Classical Physics · Physics 2017-02-07 Troy Stedman , Lilia M. Woods

A new method of cloaking is presented. For two-dimensional quasistatics it is proven how a single active exterior cloaking device can be used to shield an object from surrounding fields, yet produce very small scattered fields. The problem…

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

Recent research has uncovered a remarkable ability to manipulate and control electromagnetic fields to produce effects such as perfect imaging and spatial cloaking. To achieve spatial cloaking, the index of refraction is manipulated to flow…

We present a theory for the cloaking of arbitrarily-shaped objects and demonstrate electromagnetic scattering-cancellation through designed homogeneous coatings. First, in the small-particle limit, we expand the dipole moment of a coated…

Mesoscale and Nanoscale Physics · Physics 2014-05-26 Carlo Forestiere , Luca Dal Negro , Giovanni Miano

We first review classical results on cloaking and mirage effects for electromagnetic waves. We then show that transformation optics allows the masking of objects or produces mirages in diffusive regimes. In order to achieve this, we…

This paper explores the concept of near-cloaking in the context of time-dependent heat propagation. We show that after the lapse of a certain threshold time instance, the boundary measurements for the homogeneous heat equation are close to…

Analysis of PDEs · Mathematics 2017-12-18 Richard Craster , Sebastien Guenneau , Harsha Hutridurga , Grigorios Pavliotis

Concealing objects by making them invisible to an external electromagnetic probe is coined by the term cloaking. Cloaking devices, having numerous potential applications, are still face challenges in realization, especially in the visible…

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
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