English
Related papers

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

200 papers

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

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

A general process is proposed to experimentally design anisotropic inhomogeneous metamaterials obtained through a change of coordinate in the Helmholtz equation. The method is applied to the case of a cylindrical transformation that allows…

Computational Physics · Physics 2019-04-15 Lucas Pomot , Cédric Payan , Marcel Remillieux , Sébastien Guenneau

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

Analysis of PDEs · Mathematics 2015-09-15 Matti Lassas , Ting Zhou

We develop an optimization framework for the design of acoustic cloaks, with the aim of overcoming the limitations of usual transformation-based cloaks in terms of microstructure complexity and shape arbitrarity of the obstacle. This is…

Optimization and Control · Mathematics 2022-02-16 Sebastiano Cominelli , Davide Enrico Quadrelli , Carlo Sinigaglia , Francesco Braghin

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

We consider transformation-optics based cloaking in acoustic and electromagnetic scattering. The blueprints for an ideal cloak use singular acoustic and electromagnetic materials, posing server difficulties to both theoretical analysis and…

Analysis of PDEs · Mathematics 2014-09-03 Hongyu Liu , Gunther Uhlmann

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

We give a comprehensive study on regularized approximate electromagnetic cloaking via the transformation optics approach. The following aspects are investigated: (i) near-invisibility cloaking of passive media as well as active/radiating…

Analysis of PDEs · Mathematics 2010-09-24 Hongyu Liu , Ting Zhou

An active interior cloak is composed of a conformal array of radiating sources surrounding a target object. With proper configuration, this array radiates a field discontinuity which cancels out any scattering which occurs when the object…

Applied Physics · Physics 2024-09-26 Paris Ang , George V. Eleftheriades

We consider an ideal invisibility cloak which is illuminated by monochromatic light and which moves in vacuum at constant relativistic velocity with respect to the common inertial frame of light source and observer. We show that, in…

Optics · Physics 2016-02-03 Jad C. Halimeh , Robert T. Thompson , Martin Wegener

Here we present the results of full experimental characterization of broadband cloaking of a finite-sized metallic cylinder at X-band. The cloaking effect is characterized by measuring the bistatic scattering patterns of uncloaked and…

We propose a generalization of the two-dimensional eikonal-limit cloak derived from a conformal transformation to three dimensions. The proposed cloak is a spherical shell composed of only isotropic media; it operates in the transmission…

Optics · Physics 2012-03-28 Yaroslav Urzhumov , Nathan Landy , David R. Smith

Acoustic cloaks derived by coordinate transformation have opened up a new field of considerable interest in the last two decades. However, since perfect omnidirectional acoustic cloak relies on inhomogeneous and anisotropic materials that…

Applied Physics · Physics 2019-11-19 Mohammad Hosein Fakheri , Hooman Barati sedeh , Ali Abdolali

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

Analysis of PDEs · Mathematics 2011-01-04 Matti Lassas , Ting Zhou

Based on the concept of complementary media, we propose an invisibility cloak operating at a finite frequency that can cloak an object with a pre-specified shape and size within a certain distance outside the shell. The cloak comprises of a…

Optics · Physics 2009-11-13 Yun Lai , Huanyang Chen , Zhao-Qing Zhang , C. T. Chan

The aim of this work is to derive sharp quantitative estimates of the qualitative convergence results developed in [28] for regularized full- and partial-cloaks via the transformation-optics approach. Let $\Gamma_0$ be a compact set in…

Analysis of PDEs · Mathematics 2015-08-20 Youjun Deng , Hongyu Liu , Gunther Uhlmann

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…

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 regularized near-cloak via the transformation optics approach in the time-harmonic electromagnetic scattering is considered. This work extends the existing studies mainly in two aspects. First, it presents a near-cloak construction by…

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