Two separate teams of engineers, both conducting research into meta-materials (composites not found in nature) with the intent of developing a flexible, stretchable and tunable meta-skin, are sharing their discoveries with the world. Although the two developments revolve around the same premise—manipulating electromagnetic waves so that the surface that banquets an object becomes invisible—a few exciting differences between the teams’ approaches sets their research apart.
Engineers at Iowa State University are developing meta-skins which suppresses radar detection, meaning that this version can be seen by the naked eye, but not by cameras. The implications of such a device are many, particularly for covert operations and security, hiding sensitive layouts of electronic components and advancing the development of optical computers.
Covered by a series of small ‘electric split ring resonators’ embedded into the cloak itself—which is made of layers of silicone sheets—the meta-skin is able to tune out certain ranges of frequencies depending on how the material is stretched. This proves useful in that the material’s flexibility means it can properly adjust to accommodate for practically any frequency radiated towards it. The researchers at Iowa State proved that using meta-skin technology is more effective than traditional measures used in stealth technologies, as rather than creating a barrier surrounding an entity, the skin is able to absorb the sum total of the waves like a sponge.
The second approach, researched by scientists at UC Berkeley, also makes use of meta-materials, only that its still visible to radars and imperceptible to us normally. This particular design features arrays of golden nano-antennas which manipulate phases of light to redirect the light in such a way so that its effectively invisible to our retinas from any angle. Moreover, the team claims that the technology is easily scalable so that larger objects can be cloaked all the same.
“This is the first time a 3D object of arbitrary shape has been cloaked from visible light,” says team leader Xiang Zhang. “Our ultra-thin cloak now looks like a coat. It is easy to design and implement, and is potentially scalable for hiding macroscopic objects.”
While both implementations seem very promising indeed, they’re not without their respective flaws. The Iowa State team’s tests have shown the meta-skin was only in the 75 percent accuracy range when the frequencies were between eight to ten gigahertz. And even if the team was able to hide an object from a camera under any circumstance, it would only be from machines and not living organisms. Likewise, UC Berkeley’s team has achieved visible light cloaking, but faces the challenge of expanding their technology to include all types of light, including those perceivable by cameras.
Still, both teams’ research is impressive, and a step in the right direction. We’ll be able to say in all honestly that we’ve achieved invisibility cloaking when visible and infrared lighting can be manipulated alongside radars, and other types of lighting as well.
This article was written by Ido Lechner from PSFK and was legally licensed through the NewsCred publisher network.
