Gareth Morgan — express.co.uk Nov 11, 2013
The ultra-thin invisible clothing could allow its wearer to be completely hidden from view in a wide range of conditions.
Previous attempts at creating invisibility cloaks have only worked when seen using specific wavelengths, or colours, of light.
But a new design submitted to the science journal Physical Review Letters, promises to overcome previous problems.
Prof Andrea Alu, of the University of Texas, explained: “If you suppress scattering in one range, you need to pay the price, with interest, in some other range.
“For example, you might make a cloak that makes an object invisible to red light. But if you were illuminated by white light (containing all colours) you would actually look bright blue, and therefore stand out more.”
But he added: “Our active cloak is a completely new concept and design, aimed at beating the current limits and we show that it indeed does.
“If you want to make an object transparent at all angles and over broad bandwidths, this is a good solution. We are looking into realising this technology at the moment, but we are still at the early stages.”
His design will actively adapt to the light of the surroundings and, in theory, create a cloak that is completely invisible. It uses amplifiers to coat the surface of the object in an electric current and make it “vanish”.
Prof David Smith of Duke University, one of the team who created the first invisibility cloak in 2006, said the new design was one of the most detailed he had yet seen.
He added: “It’s an interesting implementation but as presented is probably a bit limited to certain types of objects.
“There are limitations even on active materials. It will be interesting to see if it can be experimentally realised.”
“To most people, making an object ‘invisible’ means making it transparent to visible wavelengths. And the visible spectrum is a tiny, tiny sliver of the overall electromagnetic spectrum,” he told BBC News.
“So, this finding does not necessarily preclude the Harry Potter cloak, nor does it preclude any other narrow bandwidth application of cloaking.”