Tech & Science

A Real-Life Invisibility Cloak Built Out of Nanoscale Metamaterials

In the Magazine
Scientists have figured out a way to use nanoparticles to bend light around objects, rendering them invisible ER Degginger/Science Source

As any great magician will tell you, illusions have more to do with perception than the paranormal. And though deception might seem out of place in the world of science, a team of researchers from Cambridge University have used this tenet of magic to move one step closer to developing a technology straight out of science fiction: an invisibility cloak. Only according the Ventsislav Valev, one of the scientists involved in the study, the finished product will more likely resemble a rigid, externally powered suit of armor than the pliant magical garment glamorized by Harry Potter.

As with all big projects, you have to start small—in this case, microscopic. The Cambridge researchers constructed nanoscale building blocks called “metamaterials.” These are materials, made up of nanoparticles that, due to their geometry, are capable of controlling the way light interacts with them. “We have come up with a way to produce a lot of these metamaterials in water,” Valev tells Newsweek. “It is quite ironic that we used light as a fabrication tool for a material that could one day become suitable for invisibility.”

Like a good magic trick, the metamaterials work not by changing an object’s physical properties but by altering the way the object is perceived. “You guide the light around the object. Light would follow around the object and continue as if the object was never there,” says Valev. “Through this technology it is possible to not only hide something but also make it appear as something else.”

While usable invisibility technology is “really looking far into the future,” Valev says, and the idea of complete invisibility cloaking is “very unlikely,” scientists hope this technology can one day be used to construct ultra-stealth military equipment. For now, Valev suggests at least one practical real-life application for his team’s metamaterials: security. The technology enhances light much more efficiently than a microscope, to the point where it could detect a single particle floating in the air. Valev says this could prove useful for airport inspectors by sensing traces of airborne drugs and explosives that even the most sensitive canine noses and computers can miss.

Although the team has constructed these intricate metamaterials, their functionality in a real-life setting has still “not yet been demonstrated,” Valev concedes. “This is the next step in our research.”