Meta-skin could lead to invisibility cloak

Engineers at Iowa State University may have gotten one step nearer to the talent to manufacture objects invisible with the development of what they are calling a flexible, stretchable and tunable meta-skin. They have shown that objects wrapped in the meta-skin can suppress radar detection, and they are hoping to advance the material to some day manufacture objects undetectable to both visible and infrared light.

The meta-skin is so named for the reason it is made of metamaterials (composites not discovered in nature) that can manipulate electromagnetic waves. The metaskin made at Iowa State is made with rows of what are referred to as electric split ring resonators that are embedded in layers of silicone sheets.

The resonaters are rings that are every of 2.5 mm (0.1 inch) in radius and of 0.5 mm (0.02 inches) thick. They are filled with a commercial metal alloy called galinstan that is liquid at room temperature and is often utilized to replace mercury due to its lower toxicity.

Once the rings are filled with galinstan they can trap and suppress radar waves at sure frequencies. Stretching the meta-skin changes the dimensions of the rings that changes the frequency range it can suppress, thus building the skin tunable. Tests showed radar suppression with the meta-skin was of 75 percent in the frequency range of 8 to 10 gigahertz.

The researchers involved in the project point out that the largest difference in the meta-skin and additional traditional stealth technologies that take on to turn it into a barrier to radar waves, is that the meta-skin has the future to absorb all of the radar waves, effectively acting like a radar wave sponge.

Whilst the researchers admit that cloaking an entire stealth bomber in their meta-skin to manufacture it invisible to the naked eye can need makes it to in nanomaterials, they believe their project has proven the validity of some day building that a reality.

In November of last year, scientists at Huazhong University of Science and Technology made a radar absorbent process that was in addition tunable, but it wasn’t made with any type of meta materials.

The paper outlining the work of the Iowa State Researchers was not long ago published in Science Reports.

Source: Iowa State University