A new blacker-than-black metamaterial absorbs almost all the light that hits it, heralding a new breed of stealth technology.
The material's internal structure absorbs almost all the electromagnetic radiation in a particular range, New Scientist reports. Ordinary black objects, by contrast, always reflect a bit of light. The material could be applied to all parts of the electromagnetic spectrum, meaning it could be used to make materials invisible to radar.Designed by Evgenii Narimanov of Purdue University, Mikhail Noginov of Norfolk State University in Virginia and their colleagues, the material consists of silver nanowires embedded in very thin 0.4-inch aluminum oxide squares. Their array-like structure gives them their unusual properties, New Scientist says.
The researchers tested their new black material with near-infrared radiation, just beyond the red end of the visible spectrum. When the radiation hit the polished material at less than 45 degrees from perpendicular, about 20 percent of the radiation bounced off. When they roughened the material so it wasn't smooth, less than 1 percent of the radiation bounced off.
Narimanov told New Scientist the technology would likely be used to build radar-proof stealth equipment.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.