Metascreen: Metamaterial research into light transparency

Researchers have now developed a cloak that is just micrometers thick and can hide three-dimensional objects from microwaves in their natural environment, in all directions and from all of the observers’ positions. 

Credit: Image courtesy of Institute of Physics

Their research, which has so far produced an ultralow profile cloak designed for "scattering suppression of a finite-length rod in free space", has been published in the New Journal of Physics.

Presenting their study today, 26 March, in the Institute of Physics and German Physical Society's New Journal of Physics, the researchers, from the University of Texas at Austin, have used a new, ultra-thin layer called a "metascreen."

The cloak is made of a new kind of material called a metascreen, made up of strips of copper tape attached to a flexible polycarbonate film.

Andrea Alu

The copper strips are only 66 micrometres thick and the polycarbonate film is 100 micrometres thick, and the two combined make a diagonal fishnet pattern.

It works by scattering and cancelling out incoming waves, and the researchers were able to use the cloak to shield an 18 centimetre-tall cylindrical rod from microwaves.

"When the scattered fields from the cloak and the object interfere, they cancel each other out and the overall effect is transparency and invisibility at all angles of observation," said Andrea Alu, one of the physicists.

Journal Reference: 
J C Soric, P Y Chen, A Kerkhoff, D Rainwater, K Melin, A Al. Demonstration of an ultralow profile cloak for scattering suppression of a finite-length rod in free space. New Journal of Physics, 2013; 15 (3): 033037 DOI: 10.1088/1367-2630/15/3/033037