Cloud in a cloak

Cloak/anti-cloak interactions.

Coordinate-transformation cloaking is based on the design of a metamaterial shell made of an anisotropic, spatially inhomogeneous "transformation medium" that allows rerouting the impinging wave around a given region of space. In its original version, it is generally believed that, in the ideal limit, the radiation cannot penetrate the cloaking shell (from outside to inside, and viceversa). How...

Compact-sized and broadband carpet cloak and free-space cloak.

Recently, invisible cloaks have attracted much attention due to their exciting property of invisibility, which are based on a solid theory of transformation optics and quasi-conformal mapping. Two kinds of cloaks have been proposed: free-space cloaks, which can render objects in free space invisible to incident radiation, and carpet cloaks (or ground-plane cloaks), which can hide objects under ...

A Spacetime Cloak, or a History Editor

Allan Boardman Photonics and Nonlinear Science Group, Joule Laboratory, Department of Physics, University of Salford, Salford M5 4WT, United Kingdom. (Dated: Wednesday 12 December, 2012) Abstract We introduce a recipe for producing a new type of electromagnetic cloak, the electromagnetic spacetime cloak, which conceals events rather than mere objects. Non-emitting events occurring during a rest...

Commercial confidentiality: a cloak for policy failure.

Electromagnetic Detection of a Perfect Carpet Cloak

It has been shown that a spherical invisibility cloak originally proposed by Pendry et al. can be electromagnetically detected by shooting a charged particle through it, whose underlying mechanism stems from the asymmetry of transformation optics applied to motions of photons and charges [PRL 103, 243901 (2009)]. However, the conceptual three-dimensional invisibility cloak that exactly follows ...