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Related papers: Enhanced Approximate Cloaking by SH and FSH Lining

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We consider regularized approximate cloaking for the Helmholtz equation. Various cloaking schemes have been recently proposed and extensively investigated. The existing cloaking schemes in literature are (optimally) within $|\ln\rho|^{-1}$…

Analysis of PDEs · Mathematics 2012-07-04 Hongyu Liu , Hongpeng Sun

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

In this paper, we study approximate cloaking of active devices for the Helmholtz equation in the whole space of dimension 2 or 3 using the scheme introduced by Kohn, Shen, Vogelius, and Weinstein in \cite{KohnShenVogeliusWeinstein}. More…

Mathematical Physics · Physics 2011-09-30 Hoai-Minh Nguyen

In this paper, we study approximate cloaking for the Helmholtz equation in 3d where the cloaking device is based on transformations which blow up a cylinder of fixed height and small cross section of radius $\eps$ into the cloaked region.…

Analysis of PDEs · Mathematics 2013-09-24 Hoai-Minh Nguyen

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

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

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

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 this work, we develop a general mathematical framework on regularized approximate cloaking of elastic waves governed by the Lam\'e system via the approach of transformation elastodynamics. Our study is rather comprehensive. We first…

Analysis of PDEs · Mathematics 2014-10-10 Guanghui Hu , Hongyu Liu

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

Cloaking using complementary media was suggested by Lai et al. in [8]. The study of this problem faces two difficulties. Firstly, this problem is unstable since the equations describing the phenomenon have sign changing coefficients, hence…

Analysis of PDEs · Mathematics 2015-07-08 Hoai-Minh Nguyen

In this paper, we consider two regularized transformation-optics cloaking schemes for electromagnetic (EM) waves. Both schemes are based on the blowup construction with the generating sets being, respectively, a generic curve and a planar…

Analysis of PDEs · Mathematics 2016-09-21 Youjun Deng , Hongyu Liu , Gunther Uhlmann

Invisibility cloaking in acoustic scattering via the approach of transformation optics is considered. The near-cloaks of both passive medium and active/radiating object are investigated. From a practical viewpoint, we are especially…

Analysis of PDEs · Mathematics 2012-11-12 Hongyu Liu

This paper concerns the analysis of a passive, broadband approximate cloaking scheme for the Helmholtz equation in ${\mathbb R}^d$ for $d=2$ or $d=3$. Using ideas from transformation optics, we construct an approximate cloak by ``blowing…

Analysis of PDEs · Mathematics 2023-04-20 Fioralba Cakoni , Narek Hovsepyan , Michael Vogelius

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

We develop a very general theory on the regularized approximate invisibility cloaking for the wave scattering governed by the Helmholtz equation in any space dimensions via the approach of transformation optics.

Analysis of PDEs · Mathematics 2015-03-04 Jingzhi Li , Hongyu Liu , Luca Rondi , Gunther Uhlmann

In this paper, we consider the approximate acoustic cloaking in inhomogeneous isotropic background space. By employing transformation media, together with the use of a sound-soft layer lining right outside the cloaked region, we show that…

Analysis of PDEs · Mathematics 2012-05-01 Hongyu Liu

We introduce "stochastic cloaking," where a region of space is concealed from an ensemble of diffusing particles whose individual trajectories are governed by a stochastic (Langevin) equation. Our simulations reveal how different…

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

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
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