Invisibility cloaks are not just possible, they’re becoming reality
Two types of nanotechnology, metalenses and metamaterials, could soon make Harry Potter’s invisibility cloak a reality.
For as long as human beings have been writing about fantasy, myth, and science fiction, the dream of invisibility has always been a top priority. While Star Trek brought the idea of a cloaking device into the popular consciousness, and Harry Potter brought with it the widespread idea of an actual invisibility cloak, there haven’t been many useful applications of invisibility-based technology on a large scale. In fact, the closest we’ve come to achieving actual invisibility has been through the development of stealth technology, which only bestows effective invisibility at far longer wavelengths than human eyes can perceive.
The invisibility to radar, which is microwave-to-radio wavelength electromagnetic radiation, might have been the first step, but recent developments in metamaterials have extended this even further, bending light around an object and rendering it truly undetectable. Perhaps the critical advance that could finally bring an invisibility cloak to reality occurred in 2018, in a novel material called a broadband achromatic metalens. For the first time, it rendered an object undetectable across…
