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Transformation optics (TO) is a powerful tool for the design of artiffcial materials with unprecedented optical properties. Here, we propose the approximation of TO structures of arbitrary shape by faceting, in which curved surfaces are…

We demonstrate that metamaterial devices requiring anisotropic dielectric permittivity and magnetic permeability may be emulated by specially designed tapered waveguides. This approach leads to low-loss, broadband performance. Based on this…

Rendering objects invisible to impinging acoustic waves (cloaking) and creating acoustic illusions (holography) has been attempted using active and passive approaches. While passive methods are applicable only to narrow frequency bands,…

Ground-plane cloak designs are presented, which minimize scattering of electromagnetic radiation from metallic objects in the visible spectrum. It is showed that simplified ground-plane cloaks made from only a few blocks of all-dielectric…

Classical Physics · Physics 2009-09-30 Efthymios Kallos , Christos Argyropoulos , Yang Hao

An analytical method of electromagnetic wave interactions with a general radially anisotropic cloak is established. It is able to deal with arbitrary parameters ($\epsilon_r(r)$, $\mu_r(r)$, $\epsilon_t(r)$ and $\mu_t(r)$) of a radially…

Optics · Physics 2009-10-02 Cheng-Wei Qiu , Andrey Novitsky , Hua Ma , Shaobo Qu

There has recently been considerable interest in the possibility, both theoretical and practical, of invisibility (or "cloaking") from observation by electromagnetic (EM) waves. Here, we prove invisibility, with respect to solutions of the…

Analysis of PDEs · Mathematics 2009-11-11 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

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

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 cloaks provide a way to hide an object under the detection of waves. A perfect cloak guides the incident waves through the cloaking shell without any distortion. In most cases, some important quantum degrees of freedom, e.g.…

Quantum Physics · Physics 2016-01-06 Shin-Liang Chen , Ching-Shiang Chao , Yueh-Nan Chen

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 design non-singular cloaks enabling objects to scatter waves like objects with smaller size and very different shapes. We consider the Schrodinger equation which is valid e.g. in the contexts of geometrical and quantum optics. More…

Mathematical Physics · Physics 2010-12-07 Andre Diatta , Sebastien Guenneau

Pentamode materials are elastic solids with vanishing shear modulus, and can be used cloak underwater sound with solid state and broadband merits. However, pentamode materials realized with real microstructure have inevitable small shear…

Classical Physics · Physics 2019-07-30 Yi Chen , Xiaoning Liu , Gengkai Hu

We construct a regular isotropic approximate cloak for the Maxwell system of equations. The method of transformation optics has enabled the design of electromagnetic parameters that cloak a region from external observation. However, these…

Analysis of PDEs · Mathematics 2018-05-23 Tuhin Ghosh , Ashwin Tarikere

The possibility of making an optically large (many wavelengths in diameter) object appear invisible has been a subject of many recent studies. Exact invisibility scenarios for large (relative to the wavelength) objects involve…

Optics · Physics 2015-06-11 Yaroslav Urzhumov , David R. Smith

Electromagnetic wave behaviour in an anisotropic medium with a two dimensional arbitrary geometry is studied. The aim is to trace the path of a ray in such a complex medium for the purpose of achieving cloaking (invisibility). A coordinate…

Optics · Physics 2015-11-30 H. H. Sidhwa , R. P. Aiyar , S. V. Kulkarni

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

Reducing electromagnetic scattering from an object has always been a task, inspiring efforts across disciplines such as materials science and electromagnetic theory. The pursuit of electromagnetic cloaking significantly advanced the field…

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 describe families of potentials which act as approximate cloaks for matter waves, i.e., for solutions of the time-independent Schr\"odinger equation at energy $E$, with applications to the design of ion traps. These are derived from…

Quantum Physics · Physics 2009-11-13 A. Greenleaf , Y. Kurylev , M. Lassas , G. Uhlmann

Based on the concept of the cloak generating function, we propose a numerical method to compute the invisibility performance of various quadratic spherical cloaks and obtain optimal invisibility results. A non-ideal discrete model is used…

Optics · Physics 2010-01-13 Andrey Novitsky , Cheng-Wei Qiu