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Related papers: Regularized Transformation-Optics Cloaking in Acou…

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In this paper, we consider near cloaking for the full Maxwell equations. We extend the recent results, where the quasi-static limit case and the Helmholtz equation are considered, to electromagnetic scattering problems. We construct very…

Analysis of PDEs · Mathematics 2012-12-27 Habib Ammari , Hyeonbae Kang , Hyundae Lee , Mikyoung Lim , Sanghyeon Yu

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

Ground-plane cloak designs are presented, which minimize scattering of electromagnetic radiation from metallic objects in the visible spectrum. It is showed that simplified ground-plane cloaks made from only a few blocks of all-dielectric…

Classical Physics · Physics 2009-09-30 Efthymios Kallos , Christos Argyropoulos , Yang Hao

In this Letter we develop analytical formulations to describe sound scattering in lossless medium due to 2D circular wave incident on an acoustic cloak. A perfect acoustic cloak is reflectionless and can completely hide the cloaked object…

Classical Physics · Physics 2012-05-08 Siyang Zhong , Xun Huang

Fundamental features of rotationally symmetric acoustic cloaks with anisotropic inertia are derived. Two universal relations are found to connect the radial and transverse phase speeds and the bulk modulus in the cloak. Perfect cloaking…

Fluid Dynamics · Physics 2008-02-07 Andrew N. Norris

The technique of applying form-invariant, spatial coordinate transformations of Maxwell's equations can facilitate the design of structures with unique electromagnetic or optical functionality. Here, we illustrate the transformation-optical…

We propose one kind of transformation functions for nonmagnetic invisibility cloak with minimized scattering on the basis of generalized transformation. By matching the impedance at the outer surface of the cloak, the transformations with…

Optics · Physics 2011-03-04 Lujun Huang , Daming Zhou , Jian Wang , Zhifeng Li , Xiaoshuang Chen , Wei Lu

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 has shaped up a revolutionary electromagnetic design paradigm, enabling scientists to build astonishing devices such as invisibility cloaks. Unfortunately, the application of transformation techniques to other branches…

General Relativity and Quantum Cosmology · Physics 2015-06-11 C. García-Meca , S. Carloni , C. Barceló , G. Jannes , J. Sánchez-Dehesa , A. Martínez

Here we extend the theory of space-time or event cloaking into that based on the carpet or ground-plane reflective surface. Further, by recasting and generalizing a scalar acoustic wave model into a new mathematically covariant form, we…

Optics · Physics 2015-04-27 Paul Kinsler , Martin W. McCall

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…

Acoustic metamaterials are engineered microstructures with special mechanical and acoustic properties enabling exotic effects such as wave steering, focusing and cloaking. The design of acoustic cloaks using scattering cancellation has…

Disordered Systems and Neural Networks · Physics 2022-11-15 Thang Tran , Feruza Amirkulova , Ehsan Khatami

The authors present an impedance-matched reduced version of acoustic cloaking whose mass is in a reasonable range. A layered cloak design with isotropic material is also proposed for the reduced cloak. Numerical calculations from the…

Materials Science · Physics 2008-10-07 Huan-Yang Chen , Tao Yang , Xu-Dong Luo , Hong-Ru Ma

Cloaking elastic waves has, in contrast to the cloaking of electromagnetic waves, remained a fundamental challenge: the latter successfully uses the invariance of Maxwell's equations, from which the field of transformational optics has…

Materials Science · Physics 2020-11-17 Davide Enrico Quadrelli , Richard Craster , Muamer Kadic , Francesco Braghin

Despite much interest and progress in optical spatial cloaking, a three-dimensional (3D), transmitting, continuously multidirectional cloak in the visible regime has not yet been demonstrated. Here we experimentally demonstrate such a cloak…

Optics · Physics 2015-03-10 Joseph S. Choi , John C. Howell

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

Acoustic invisibility of a cloaking system in turbulent uids has been poorly understood. Here we show that evident scattering would appear in turbulent wakes owing to the submergence of a classical cloaking device. The inherent mechanism is…

Fluid Dynamics · Physics 2016-11-25 Xun Huang , Siyang Zhong

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 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

In this article we consider cloaking for a quasi-linear elliptic partial differential equation of divergence type defined on a bounded domain in $\mathbb{R}^N$ for $N=2,3$. We show that a perfect cloak can be obtained via a singular change…

Analysis of PDEs · Mathematics 2019-08-01 Tuhin Ghosh , Karthik Iyer