How To Make Human-Sized Invisibility Cloaks
Thanks to a new printing method, we are now able to produce large sheets of metamaterials, a new class of materials that is designed to interact with light much differently than natural materials can. Metamaterials are made up of intricately patterned layers, often made of…you guessed it, metals.
The patterns must be on the same scale as the wavelength of the light they’re designed to interact with and must be of nano-size. Although researchers have been able to make invisibility sheets in the past, they were so small that it wasn’t a practical cloak, until now.
John Rogers, professor of materials science and engineering at University of Illinois developed a stamp-based printing method for generating large pieces of metamaterial that bend near-infrared light in the opposite direction. These materials with a negative index of refraction on promising for researchers to create night-vision invisibility cloaks. Below is the process Rogers uses to create the sheet, as TechnologyReview reports.
Rogers says he’s made metamaterial sheets a few inches per side, but by using more than one stamp he expects to increase that to square feet. And, he says, the stamped materials actually have better optical properties than metamaterials made using traditional methods.
Here is a video that explains the same concept with the invisibility cloaks.