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Related papers: Active Cloaking

200 papers

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…

The possibility of using plasmonic covers to drastically reduce the total scattering cross section of spherical and cylindrical objects is discussed. While it is intuitively expected that increasing the physical size of an object may lead…

Materials Science · Physics 2007-05-23 Andrea Alu , Nader Engheta

A cylindrical plasmonic structure with a concentric core exhibits an anomalous localized resonance which results in cloaking effects. Here we show that, if the structure has an eccentric core, a new kind of shielding effect can happen. In…

Mathematical Physics · Physics 2017-02-24 Sanghyeon Yu , Mikyoung Lim

We propose a general method to arbitrarily manipulate an electromagnetic wave propagating in a two-dimensional medium, without introducing any scattering. This leads to a whole class of isotropic spatially varying permittivity and…

The optical theorem relates the total scattering cross-section of a given structure with its forward scattering, but does not impose any restrictions on other directions. Strong backward-forward asymmetry in scattering could be achieved by…

Other Condensed Matter · Physics 2016-11-22 Vitali Kozlov , Dmitry Filonov , Alexander S. Shalin , Ben Z. Steinberg , Pavel Ginzburg

Transformation media theory, which steers waves in solids via an effective geometry induced by a refractive material (Fermat's principle of least action), provides a means of controlling vibrations and elastic waves beyond the traditional…

Applied Physics · Physics 2018-08-01 Sophia R. Sklan , Ronald Y. S. Pak , Baowen Li

An invisibility cloak that can hide an arbitrary object external to the cloak itself has not been devised before. In this Letter, we introduce a novel way to design a remote cloaking device that makes any object located at a certain…

Scattering of nonstationary electromagnetic fields from axially symmetrical bodies is numerically investigated. Simulations are performed using the time- and frequency-domain approaches. Computational results obtained for a finite perfectly…

Mathematical Physics · Physics 2007-05-23 I. G. Efimova

We propose two approaches to cloak the spin waves (magnons) by investigating magnetization dynamics. One approach is based on a spatially inhomogeneous anisotropic magnetic moment tensor. The other mechanism is using a spatially…

Mesoscale and Nanoscale Physics · Physics 2016-04-20 Mehrdad Elyasi , Charanjit S. Bhatia , Cheng-Wei Qiu , Hyunsoo Yang

Cloaking elastic waves has, in contrast to the cloaking of electromagnetic waves, remained a fundamental challenge: the latter successfully uses the invariance of Maxwell's equations, from which the field of transformational optics has…

Materials Science · Physics 2020-11-17 Davide Enrico Quadrelli , Richard Craster , Muamer Kadic , Francesco Braghin

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…

Trapped samples of ultracold molecules are often short-lived, because close collisions between them result in trap loss. We investigate the use of shielding with static electric fields to create repulsive barriers between polar molecules to…

Quantum Gases · Physics 2024-02-20 Bijit Mukherjee , Jeremy M. Hutson

Carpets under consideration here, in the context of pressure acoustic waves propagating in a compressible fluid, do not touch the ground: they levitate in mid-air (or float in mid-water), which leads to approximate cloaking for an object…

Optics · Physics 2010-05-19 Andre Diatta , Guillaume Dupont , Sebastien Guenneau , Stefan Enoch

We derive and discuss general physical bounds on the electromagnetic scattering and absorption of passive structures. Our theory, based on passivity and power conservation, quantifies the minimum and maximum allowed scattering for an object…

Optics · Physics 2015-06-17 Romain Fleury , Jason Soric , Andrea Alu

The intriguing concept of "anti-cloaking" has been recently introduced within the framework of transformation optics (TO), first as a "countermeasure" to invisibility-cloaking (i.e., to restore the scattering response of a cloaked target),…

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

Cloaking of static magnetic fields by a finite thickness type-II superconductor tube surrounded by a coaxial paramagnet shell is studied. On the basis of exact solutions to the London and Maxwell equations, it is shown that perfect cloaking…

Superconductivity · Physics 2014-02-17 S. V. Yampolskii , Y. A. Genenko

In this paper we explored the scattering behavior of thin cylinders made of LHM and coated by a monoatomic graphene layer. A spectral tunability of the resonance peaks is evidenced by altering the chemical potential of the graphene coating,…

We demonstrate three simple cloaking devices that can hide very large spatial objects over the entire visible spectrum using only passive, off-the-shelf optics. The cloaked region for all of the devices exceeds 10^6 mm3 with the largest…

Optics · Physics 2015-06-16 John C. Howell , J. Benjamin Howell

In this paper, we propose a new electromagnetic (EM) GL double layered cloak. The GL double layered cloak is consist of two sphere annular layers, $R_1 \le r \le R_2$ and $R_2 \le r \le R_3$. Two type cloak materials are proposed and…

Optics · Physics 2009-04-22 Ganquan Xie , Jianhua Li , Feng Xie , Lee Xie