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Related papers: Acoustic cloaking: geometric transform, homogeniza…

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Concealing an object from incoming waves (light and/or sound) remained science fiction for a long time due to the absence of wave-shielding materials in nature. Yet, the invention of artificial materials and new physical principles for…

Applied Physics · Physics 2021-02-17 Waqas W. Ahmed , Mohamed Farhat , Xiangliang Zhang , Ying Wu

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

Cloaking using complementary media was suggested by Lai et al. This was proved in the quasistatic regime by H. M. Nguyen. One of the difficulties in the study of this problem is the appearance of the localized resonance, i.e., the fields…

Analysis of PDEs · Mathematics 2015-04-29 Hoai-Minh Nguyen , Loc Hoang Nguyen

Using the framework of transformation optics, this paper presents a detailed analysis of a non-singular square cloak for acoustic, out-of-plane shear elastic, and electromagnetic waves. The generating map is examined in detail and linked to…

Mathematical Physics · Physics 2014-01-30 DJ Colquitt , IS Jones , NV Movchan , AB Movchan M Brun , RC McPhedran

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 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

Coordinate-transformation cloaking is based on the design of a metamaterial shell made of an anisotropic, spatially inhomogeneous "transformation medium" that allows rerouting the impinging wave around a given region of space. In its…

We consider approximate cloaking from a regularization viewpoint introduced in [13] for EIT and further investigated in [12] [17] for the Helmholtz equation. The cloaking schemes in [12] and [17] are shown to be (optimally) within…

Analysis of PDEs · Mathematics 2015-05-30 Jingzhi Li , Hongyu Liu , Hongpeng Sun

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

This is a survey of approximate cloaking using transformation optics for acoustic and electromagnetic waves.

Analysis of PDEs · Mathematics 2019-02-01 Hoai-Minh Nguyen , Michael S. Vogelius

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

From ancient to modern times, acoustic structures have been used to control the propagation of acoustic waves. However, the design of the acoustic structures has remained widely a time-consuming and computational resource-consuming…

Sound · Computer Science 2024-11-12 Xuecong Sun , Han Jia , Yuzhen Yang , Han Zhao , Yafeng Bi , Zhaoyong Sun , Jun Yang

Recently, researchers have proposed several carpet cloaking designs that are able to hide a real object under a bump in a way that it is perceived as a flat ground plane. Here, we present a method to design two-dimensional isotropic carpet…

Optics · Physics 2012-02-21 T. Ochiai , J. C. Nacher

A method is proposed to design arbitrary shaped two dimensional (2D) isotropic-inertia acoustic cloaks without singularity. The method is based on the deformation view of the transformation method, where the transformation tensor A is…

Classical Physics · Physics 2011-06-01 Jin Hu , Xiaoming Zhou , Gengkai Hu

This paper is concerned with the invisibility cloaking in acoustic wave scattering from a new perspective. We are especially interested in achieving the invisibility cloaking by completely regular and isotropic mediums. It is shown that an…

Analysis of PDEs · Mathematics 2016-04-20 Xia Ji , Hongyu Liu

We experimentally demonstrated an alternative approach of invisibility cloaking that can combine technical advantages of all current major cloaking strategies in a unified manner and thus can solve bottlenecks of individual strategies. A…

In transformation optics, the space transformation is viewed as the deformation of a material. The permittivity and permeability tensors in the transformed space are found to correlate with the deformation field of the material. By solving…

Classical Physics · Physics 2009-11-13 Jin Hu , Xiaoming Zhou , Gengkai Hu

In this work, we consider the problem of optimal design of an acoustic cloak under uncertainty and develop scalable approximation and optimization methods to solve this problem. The design variable is taken as an infinite-dimensional…

Optimization and Control · Mathematics 2021-03-17 Peng Chen , Michael R. Haberman , Omar Ghattas

We study the approximate cloaking via transformation optics for electromagnetic waves in the time harmonic regime in which the cloaking device {\it only} consists of a layer constructed by the mapping technique. Due to the fact that…

Analysis of PDEs · Mathematics 2018-11-02 Hoai-Minh Nguyen , Loc Tran

Elastic material with its elastic tensor losing minor symmetry is considered impossible without introducing artificially body torque. Here we demonstrate the feasibility of such material by introducing rotational resonance, the amplified…

Classical Physics · Physics 2020-01-08 Hongkuan Zhang , Yi Chen , Xiaoning Liu , Gengkai Hu
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