American physicists of the University of Texas at Austin, published the results of work to create a cloak of invisibility. Although the work in this direction were made long ago, but the distinguishing feature of the current study was the use of new technology - plasma resonators. Prior to that, the scientists managed to achieve only partial invisibility of objects with the help of technology based on the properties of composite metamaterilov, an important property, which is a negative refractive index. Created with the help of this technology invisibility cloak had a number of shortcomings: the invisibility was achieved only at certain viewing angles and at a certain temperature environment.
In its work under the direction of Andrea Alu, physicists have created a thin strip of material to absorb waves of the visible range of light, converting it into heat or radiation of the electromagnetic spectrum. Strips of material made from copper or silver. In carrying out experiments on the metal surface appear quasiparticles called plasmons: an effect of the collective oscillations of electrons. Scientists were able to use this effect to create a new, in their properties, the metamaterial.
Cloak of Invisibility like "pushes" waves at microwave frequencies emanating from the cloak and the hidden object, which appeared in the role of small cylinder of plastic, which leads to mutual destruction of the waves, thus achieved the effect of invisibility in a certain region of the spectrum. The results of not deceive the expectations of scientists. Maximum suppression of scattered radiation in a range of 2.7 GHz to 3.8 GHz, reaching its peak at 3, 1 GHz. The subject remained invisible when the observation angle and the distance between him and his cloak. Scientists are confident that this technology can hide objects of complex shape from the rays of the visible spectrum of light. In this case, the allowable size of objects will depend on the frequency at which the cloak works.