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Related papers: Ground-Plane Quasi-Cloaking for Free Space

200 papers

All the thermal cloaks reported in the literature can be used to thermally hide an object inside the cloak. However, a common limitation of this kind of thermal cloaks is that the cloaked object cannot feel the external heat flow since it…

Materials Science · Physics 2013-12-12 Y. Gao , J. P. Huang

We propose a general method to circumvent the singularity of arbitrary 2D cloaks, which arises from infinitely large values of material parameters at inner boundaries. The presented method is based on the deformation view of the…

Optics · Physics 2009-07-14 Jin Hu , Xiaoming Zhou , Gengkai Hu

Cloaking using a volumetric structure composed of stacked two-dimensional transmission-line networks is verified with measurements. The measurements are done in a waveguide, in which an array of metallic cylinders is inserted causing a…

Invisible cloaking is one of major outcomes of the metamaterial research, but the practical potential, in particular for high frequencies (e.g., microwave to visible light), is fatally challenged by the complex material properties they…

Optics · Physics 2015-11-26 Jianfei Zhu , Wei Jiang , Yichao Liu , Ge Yin , Jun Yuan , Sailing He , Yungui Ma

We propose a class of line-transformed cylindrical cloaks which have easily-realizable constitutive parameters. The scattering properties of such cloaks have been investigated numerically for both transverse-electric (TE) and…

Optics · Physics 2015-05-14 Wei Xiang Jiang , Hui Feng Ma , Qiang Cheng , Tie Jun Cui

A new method of cloaking is presented. For two-dimensional quasistatics it is proven how a single active exterior cloaking device can be used to shield an object from surrounding fields, yet produce very small scattered fields. The problem…

Mathematical Physics · Physics 2015-06-03 Fernando Guevara Vasquez , Graeme W. Milton , Daniel Onofrei

The ability to render objects invisible using a cloak - not detectable by an external observer - for concealing objects has been a tantalizing goal1-6. Here, we demonstrate a cloak operating in the near infrared at a wavelength of 1550 nm.…

Optics · Physics 2009-09-30 Lucas H. Gabrielli , Jaime Cardenas , Carl B. Poitras , Michal Lipson

Spacetime or `event' cloaking was recently introduced as a concept, and the theoretical design for such a cloak was presented for illumination by electromagnetic waves [McCall, Favaro, Kinsler, Boardman 2011]. Here we describe how event…

Optics · Physics 2015-04-27 Paul Kinsler , Martin W. McCall

In light of the surge in popularity of electromagnetic cloaking devices, we consider whether it is possible to use gravitational lensing to cloak a volume of spacetime. A metric for such a spacetime geometry is presented, and its geometric…

General Relativity and Quantum Cosmology · Physics 2012-10-30 Benjamin K. Tippett

Using a sum rule, we derive new bounds on Herglotz functions that generalize those given in (Gustafson and Sj\"oberg 2010) and (Bernland, Luger and Gustafson 2011). These bounds apply to a wide class of linear passive systems such as…

Mathematical Physics · Physics 2017-08-02 Maxence Cassier , Graeme W. Milton

Invisibility cloak capable of hiding an object can be achieved by properly manipulating electromagnetic field. Such a remarkable ability has been shown in transformation and ray optics. Alternatively, it may be realistic to create a spatial…

An acoustic cloak envelopes an object so that sound incident from all directions passes through and around the cloak as though the object were not present. A theory of acoustic cloaking is developed using the transformation or…

Materials Science · Physics 2008-07-13 Andrew N. Norris

Steering waves in elastic solids is more demanding than steering waves in electromagnetism or acoustics. As a result, designing material distributions which are the counterpart of optical invisibility cloaks in elasticity poses a major…

Materials Science · Physics 2019-06-10 Muamer Kadic , Martin Wegener , Andre Nicolet , Frederic Zolla , Sebastien Guenneau , Andre Diatta

The key challenge in current research into electromagnetic cloaking is to achieve invisibility over an extended bandwidth. There has been significant progress towards this using the idea of cloaking by sweeping under the carpet of Li and…

In the past few years, carpet cloaking attracted interests because of its feasibility at optical frequencies and potential in stealth technologies. Metasurfaces have been proposed as a method to engineer ultra-thin carpet cloaking surfaces…

Optics · Physics 2019-06-26 L. Y. Hsu , A. Ndao , B. Kanté

Non-Euclidean geometry combined with transformation optics has recently led to the proposal of an invisibility cloak that avoids optical singularities and therefore can work, in principle, in a broad band of the spectrum [U. Leonhardt and…

Optics · Physics 2014-06-16 Tomas Tyc , Huanyang Chen , Che Ting Chan , Ulf Leonhardt

We prove that, for arbitrary three-dimensional transformation-based invisibility cloaking of an object above a ground plane or of isolated object, there are practical constraints that increase with the object size. In particular, we show…

Optics · Physics 2011-08-15 Hila Hashemi , A. Oskooi , J. D. Joannopoulos , Steven G. Johnson

A laser cooling method for trapped atoms is described which achieves ground state cooling by exploiting quantum interference in a driven Lambda-shaped arrangement of atomic levels. The scheme is technically simpler than existing methods of…

Quantum Physics · Physics 2010-03-26 Giovanna Morigi , Juergen Eschner , Christoph H. Keitel

This is a survey of approximate cloaking using transformation optics for acoustic and electromagnetic waves.

Analysis of PDEs · Mathematics 2019-02-01 Hoai-Minh Nguyen , Michael S. Vogelius

This note is a comment on a recent article [Tsakmakidis, et al., Nat Commun 10 (2019)] that presents a thought-provoking proposal to overcome the bandwidth restrictions of invisibility cloaks based on using media that support superluminal…