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Related papers: Ground-Plane Quasi-Cloaking for Free Space

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We propose a scheme of acoustic spherical cloaking by means of background irrotational flow in compressible fluid. The background flow forms a virtual curved spacetime and guides the sound waves bypass the cloaked objects. To satisfy the…

Classical Physics · Physics 2016-08-24 Ruo-Yang Zhang , Qing Zhao , Mo-Lin Ge

It is shown that nonlinear elastic pre-stress of neo-Hookean hyperelastic materials can be used as a mechanism to generate finite cloaks and thus render objects near-invisible to incoming antiplane elastic waves. This approach appears to…

Classical Physics · Physics 2012-04-26 William J. Parnell , Andrew N. Norris , Tom Shearer

Mechanical cloaks are materials engineered to manipulate the elastic response around objects to make them indistinguishable from their homogeneous surroundings. Typically, methods based on material-parameter transformations are used to…

Applied Physics · Physics 2022-04-27 Liwei Wang , Jagannadh Boddapati , Ke Liu , Ping Zhu , Chiara Daraio , Wei Chen

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…

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

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

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 introduce the concept and practical design of broadband, ultrathin cloaks based on non-Foster, negatively capacitive metasurfaces. By using properly tailored, active frequency-selective screens conformal to an object, within the realm of…

Optics · Physics 2013-12-05 Pai-Yen Chen , Christos Argyropoulos , Andrea Alu

A near-perfect, non-singular cylindrical invisibility cloak with diamond cross section is achieved by a two-step coordinate transformation. A small line segment is stretched and then blown up into a diamond space, and finally the cloak…

Optics · Physics 2011-12-21 Wei Li , Jianguo Guan , Zhigang Sun , Wei Wang , Qingjie Zhang

In this paper, we propose a novel electromagnetic (EM) cloaking structure that consists of two annular layers between three spherical shells and model its performance numerically and theoretically by using a Global and Local EM field (GL)…

Optics · Physics 2017-01-02 Ganquan Xie , Jianhua Li , Feng Xie , Lee Xie

Near-field scanning optical microscopy is a powerful technique for imaging below the diffraction limit, which has been extensively used in bio-medical imaging and nanophotonics. However, when the electromagnetic fields under measurement are…

We design three dimensional electromagnetic cloaks, starting from a small region of complex shape instead of a point. We derive the expression of a transformation matrix describing an objet with a surface of revolution and its associated…

Computational Physics · Physics 2015-05-18 G. Dupont , S. Guenneau , S. Enoch

In this paper, we consider two regularized transformation-optics cloaking schemes for electromagnetic (EM) waves. Both schemes are based on the blowup construction with the generating sets being, respectively, a generic curve and a planar…

Analysis of PDEs · Mathematics 2016-09-21 Youjun Deng , Hongyu Liu , Gunther Uhlmann

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

Optics · Physics 2009-11-13 A. Greenleaf , Y. Kurylev , M. Lassas , G. Uhlmann

The concept of an invisibility cloak is a fixture of science fiction, fantasy, and the collective imagination. However, a real device that could hide an object from sight in visible light from absolutely any viewpoint would be extremely…

In this paper, we propose a new electromagnetic (EM) GL double layered cloak. The GL double layered cloak is consist of two sphere annular layers, $R_1 \le r \le R_2$ and $R_2 \le r \le R_3$. Two type cloak materials are proposed and…

Optics · Physics 2009-04-22 Ganquan Xie , Jianhua Li , Feng Xie , Lee Xie

We present a novel approach of modelling surface light scattering in the context of freeform optical design. The model relies on energy conservation and optimal transport theory. For isotropic scattering in cylindrically or rotationally…

Carpets under consideration here, in the context of pressure acoustic waves propagating in a compressible fluid, do not touch the ground: they levitate in mid-air (or float in mid-water), which leads to approximate cloaking for an object…

Optics · Physics 2010-05-19 Andre Diatta , Guillaume Dupont , Sebastien Guenneau , Stefan Enoch

Optical metamaterials have the potential to control the flow of light at will which may lead to spectacular applications as the perfect lens or the cloaking device. Both of these optical elements require invariant effective material…

Optics · Physics 2009-09-09 Thomas Paul , Christoph Menzel , Carsten Rockstuhl , Falk Lederer

We introduce a solid material that is itself invisible, possessing identical electromagnetic properties as air (i.e. not a cloak) at a desired frequency. Such a material could provide improved mechanical stability, electrical conduction and…

Optics · Physics 2016-02-17 Dexin Ye , Ling Lu , John D. Joannopoulos , Marin Soljačić , Lixin Ran
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