Metamaterials After another news story about a “Harry Potter invisibility cloak”, we take a look at the science behind metamaterials. Science Invisibility has long been employed in works of science fiction and fantasy, from “cloaking devices” on spaceships in the various Star Trek series to Harry Potter’s magic cloak. But physicists are beginning to think they can actually make devices with just these properties. To achieve the feat of “cloaking” an object, they have developed what are known as “metamaterials”, some of which can bend electromagnetic radiation, such as light, around an object, giving the appearance that it isn’t there at all. The first examples only worked with long-wavelength radiation such as microwaves. One small device that made small objects invisible to near-infrared radiation and worked in three dimensions was unveiled by physicists from the UK and Germany earlier this year. Its creators claimed there was nothing stopping them from scaling t