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Related papers: Acoustic cloaking: geometric transform, homogeniza…

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Hitherto acoustic cloaking devices, which conceal objects externally, have depended on the objects' characteristics. Despite previous works, we design cloaking device placed neighbor an arbitrary object and makes it invisible without the…

Applied Physics · Physics 2019-05-01 Zahra Basiri , Mohammad Hosein Fakheri , Ali Abdolali

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

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

Application of transformation theory to underwater acoustics has been a challenging task because highly anisotropic density is unachievable in water. A possible strategy is to exploit anisotropic modulus rather than density, while has not…

Classical Physics · Physics 2017-06-07 Yi Chen , Mingye Zheng , Xiaoning Liu , Yafeng Bi , Zhaoyong Sun , Ping Xiang , Jun Yang , Gengkai Hu

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…

Electromagnetic cloaks are devices that can be used to reduce the total scattering cross section of various objects. An ideal cloak removes all scattering from an object and thus makes this object "invisible" to the electromagnetic fields…

Optics · Physics 2015-05-14 Pekka Alitalo , Henrik Kettunen , Sergei Tretyakov

Invisibility or unhearability cloaks have been made possible by using metamaterials making light or sound flow around obstacle without the trace of reflections or shadows. Metamaterials are known for being flexible building units that can…

Based on the transformation optics, a novel transmission-line (TL) approach to realize invisibility cloaking using planar anisotropic metamaterials (MTMs) is proposed. The two-dimensional cylindrical cloaks are modeled based on…

Classical Physics · Physics 2015-05-14 Xiao Liu , Chao Li , Kan Yao , Xiankun Meng , Fang Li

We theoretically and numerically demonstrate that hydrodynamic cloaking can be achieved by simply adjusting the geometric depth of a region surrounding an object in microscale flow, rendering the external flow field undisturbed. Using the…

Fluid Dynamics · Physics 2025-06-23 Hongyu Liu , Zhi-Qiang Miao , Guang-Hui Zheng

In a recent Letter, Cummer et al. give a description of material parameters for acoustic wave propagation giving rise to a 3D spherical cloak, and verify the cloaking phenomenon on the level of scattering coefficients. A similar…

Optics · Physics 2008-01-23 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

Invisibility cloaking not only catches the human imagination, but also promises fascinating applications in optics and photonics. By manipulating electromagnetic waves with metamaterials, researchers have been able to realize…

The concept of cloaking -- hiding objects from external detection -- has seen wide success in linear systems. Yet, translating these advancements to nonlinear mechanical systems remains an open challenge. Here, we present a new approach to…

The approximate cloaking is investigated for time-harmonic Maxwell's equations via the approach of transformation optics. The problem is reduced to certain boundary effect estimates due to an inhomogeneous electromagnetic inclusion with an…

Analysis of PDEs · Mathematics 2013-05-10 Gang Bao , Hongyu Liu

Invisible cloak has long captivated the popular conjecture and attracted intensive research in various communities of wave dynamics, e.g., optics, electromagnetics, acoustics, etc. However, their inhomogeneous and extreme parameters imposed…

Materials Science · Physics 2013-02-05 Tiancheng Han , Baowen Li , Cheng-Wei Qiu

Based on a coordinate transformation approach, Pendry {\it et al.} have reported electromagnetically anisotropic and inhomogeneous shells that, in theory, completely shield an interior structure of arbitrary size from electromagnetic fields…

In this paper, we present the design of cylindrical and spherical electromagnetic cloaks working at visible frequencies. The cloak design is based on the employment of layered structures consisting of alternating plasmonic and non-plasmonic…

Optics · Physics 2008-08-01 Filiberto Bilotti , Simone Tricarico , Lucio Vegni

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

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

The acoustic cloaking theory of Norris (2008) permits considerable freedom in choosing the transformation function f from physical to virtual space. The standard process for defining cloak materials is to first define f and then evaluate…

Materials Science · Physics 2012-10-05 Nachiket H. Gokhale , Jeffrey L. Cipolla , Andrew N. Norris

Invisibility devices based on coordinate transformation have opened up a new field of considerable interest. Such a device is proposed to render the hidden object undetectable under the flow of light or sound, by guiding and controlling the…

Optics · Physics 2015-05-20 Shu Zhang , Chunguang Xia , Nicholas Fang