Researchers have creating a cloaking device that redirects approaching waves around an object without scattering the wave energy, essentially making it invisible to devices like sonar.
Whether the invisibility cloak in Harry Potter, the cloaking device in Star Trek, or the various government agencies investing in invisibility R&D, humans have long fantasized about technology capable of rendering one undetectable. Scientists have been working at actually making this fantasy a reality, and a group of researchers was recently successful.
Amanda D. Hanford, a researcher at Pennsylvania State University, and her colleagues made a design for an underwater cloaking device that uses metamaterials—synthetic composites that have structural components not found in nature—to obscure objects. But here’s the catch: this device makes objects invisible to sonar, but not the naked eye.
Still, it’s a remarkable feat. Hanford and her team created a three-foot tall pyramid of perforated plates and, when they placed it underwater and tried to detect it using sound waves, they couldn’t. It was as if the sound waves moved right through it without even realizing the object was there.
“These materials sound like a totally abstract concept, but the math is showing us that these properties are possible,” Hanford said in a press release. “So, we are working to open the floodgates to see what we can create with these materials.”
And since a lot of the “searching” we do underwater is using technology rather than the naked eye, this kind of “invisibility” could be just as useful as vanishing altogether.