Broadband exterior cloaking

Broadband exterior cloaking.

It is shown how a recently proposed method of cloaking is effective over a broad range of frequencies. The method is based on three or more active devices. The devices, while not radiating significantly, create a "quiet zone" between the devices where the wave amplitude is small. Objects placed within this region are virtually invisible. The cloaking is demonstrated by simulations with a broadb...

Active Exterior Cloaking

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 is reduced to finding a polynomial which is approximately one within one disk and zero within a second disk, and such a polynomial is constructed. For the tw...

Source amplitudes for active exterior cloaking

Broadband cloaking in stratified seas.

Here we show that floating objects in stratified fluids can be cloaked against broadband incident waves by properly architecting the bottom corrugations. The presented invisibility cloaking of gravity waves is achieved utilizing a nonlinear resonance concept that occurs between surface and internal waves mediated by the bottom topography. Our cloak bends wave rays from the surface into the body...

Transformation optics: approaching broadband electromagnetic cloaking

An approach to broadband cloaking of light waves is analysed for a simplified case of a scaling transformation for a general cylindrical coordinate system. The proposed approach requires metamaterials with specifically engineered dispersion. The restriction on the signs of gradients in the dispersion dependencies of the dielectric permittivity and the magnetic permeability for different operati...