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Related papers: Acoustic cloaking in 2D and 3D using finite mass

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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…

We present a proof of concept design for a structured square cloak enclosing a void in an elastic lattice, subjected to flexural vibrations. In addition to the theoretical design, we fabricate and experimentally test an elastic invisibility…

Materials Science · Physics 2016-12-28 D. Misseroni , D. J. Colquitt , A. B. Movchan , N. V. Movchan , I. S. Jones

We outline a general method of constructing finite-range cloaking potentials which render a given finite-range real or complex potential $v(x)$ unidirectionally reflectionless or invisible at a wavenumber $k_0$ of our choice. We give…

Classical Physics · Physics 2015-06-10 Ali Mostafazadeh

We consider the propagation of acoustic waves in a 2D waveguide unbounded in one direction and containing a compact obstacle. The wavenumber is fixed so that only one mode can propagate. The goal of this work is to propose a method to cloak…

Analysis of PDEs · Mathematics 2022-04-27 Lucas Chesnel , Jérémy Heleine , Sergei A. Nazarov

In this paper we study point transformed electromagnetic invisibility cloaks in transformation media that are obtained by transformation from general anisotropic media. We assume that there are several cloaks located in different points in…

Optics · Physics 2009-11-13 Ricardo Weder

We consider the problem of hiding non-stationary objects from acoustic detection in a two-dimensional environment, where both the object's impedance and the properties of the detection signal may vary during operation. The detection signal…

Applied Physics · Physics 2023-07-19 Or Lasri , Lea Sirota

A metamaterial slab of anisotropic mass with one diagonal component being infinity and the other being zero is demonstrated to behave as a superlens for acoustic imaging beyond the diffraction limit. The underlying mechanism for…

Materials Science · Physics 2015-05-28 Xiaoming Zhou , Gengkai Hu

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

In an electromagnetic cloak based on a transformation approach, reduced sets of material properties are generally favored due to their easier implementation in reality, although a seemingly inevitable drawback of undesired reflection exists…

An elastic cloak hides a hole or an inhomogeneity from elastic fields. In this paper, a formulation of the optimal design of elastic cloaks based on the adjoint state method, in which the balance of linear momentum is enforced as a…

Computational Engineering, Finance, and Science · Computer Science 2023-05-31 Fabio Sozio , Mostafa Faghih Shojaei , Arash Yavari

We consider a time-harmonic wave problem, appearing for example in water-waves and in acoustics, in a setting such that the analysis reduces to the study of a 2D waveguide problem with a Neumann boundary condition. The geometry is symmetric…

Analysis of PDEs · Mathematics 2018-05-31 Lucas Chesnel , Sergei A. Nazarov , Vincent Pagneux

This paper is concerned with the invisibility cloaking in electromagnetic wave scattering from a new perspective. We are especially interested in achieving the invisibility cloaking by completely regular and isotropic mediums. Our study is…

Mathematical Physics · Physics 2017-01-20 Jingzhi Li , Xiaofei Li , Hongyu Liu , Yuliang Wang

We derive the elastic properties of a cylindrical cloak for in-plane coupled shear and pressure waves. The cloak is characterized by a rank 4 elasticity tensor with 16 spatially varying entries which are deduced from a geometric transform.…

Materials Science · Physics 2009-11-13 Michele Brun , Sebastien Guenneau , Alexander B. Movchan

This paper is concerned with the elastic near cloaking for the Lam\'e system in three-dimensions using the notion of elastic scattering coefficients (ESC). Accordingly, the ESC of arbitrary three-dimensional objects are designed and some of…

Mathematical Physics · Physics 2020-12-08 Hongyu Liu , Wing Yan Tsui , Abdul Wahab , Xianchao Wang

Invisibility cloaking imposes strict conditions on the refractive index profiles of cloaking media that must be satisfied to successfully hide an object. The first experimental demonstrations of cloaking used artificial metamaterials to…

Optics · Physics 2012-06-19 Darran F. Milne , Natalia Korolkova

The concept of scattering coefficients has played a pivotal role in a broad range of inverse scattering and imaging problems in acoustic, and electromagnetic media. In view of their promising applications in inverse problems related to…

Mathematical Physics · Physics 2017-01-17 Tasawar Abbas , Habib Ammari , Guanghui Hu , Abdul Wahab , Jong Chul Ye

A radial-dependent dispersive finite-difference time-domain (FDTD) method is proposed to simulate electromagnetic cloaking devices. The Drude dispersion model is applied to model the electromagnetic characteristics of the cloaking medium.…

Classical Physics · Physics 2009-05-13 Christos Argyropoulos , Yan Zhao , Yang Hao

M\"uhlig et. al. propose and fabricate a "cloak" comprised of nano-particles on the surface of a sub-wavelength silica sphere. However, the coating only reduces the scattered fields. This is achieved by increased absorption, such that total…

We formulate the problems of nonlinear and linear elastodynamics transformation cloaking in a geometric framework. It is noted that a cloaking transformation is neither a spatial nor a referential change of frame (coordinates); a cloaking…

Soft Condensed Matter · Physics 2019-04-17 Arash Yavari , Ashkan Golgoon

We experimentally report perfect acoustic absorption through the interplay of the inherent losses and transparent modes with high $Q$ factor. These modes are generated in a two-port, one-dimensional waveguide which is side-loaded by…

Classical Physics · Physics 2015-09-07 A. Merkel , G. Theocharis , O. Richoux , V. Romero-García , V. Pagneux