Harry Potter’s ‘invisibility cloak’ has moved a step closer to reality thanks to European Commission funded nanotechnology research.
In a statement published earlier this week, the European Commission revealed how scientists from Germany, Greece, Turkey and the UK have succeeded in tailoring the flow of light using nanotechnology, opening the way not only for potential applications in lenses and optical circuitry but also to exotic three dimensional devices such as ‘invisibility cloaks’. Although currently limited to cloaking objects of sub-millimetre size, the project has delivered a key proof-of-principle for engineering the optical properties of materials in ways believed impossible until now.
The project is part of the Commission’s initiative to boost high-risk ICT research in future and emerging information technologies, an objective of the Digital Agenda for Europe.
Neelie Kroes, Vice President of the European Commission for the Digital Agenda, said: “I am amazed by the ingenuity of European researchers. This project has achieved in real life what we knew only from special effects in the cinema. Such cutting edge research is crucial to laying the foundations for new technologies essential for Europe’s competitiveness.”
Scientists in the PHOME project designed and created ‘photonic meta-materials’ which influence the behaviour of light rays. The breakthrough is based on the principle of transformation optics which was pioneered by the team behind the project.
The ‘invisibility cloak’ itself is made up of very small rods just a few hundred nanometres across that are arranged into a structure resembling a woodpile.
The rods are carefully arranged so that they are able to partially bend light waves.
By changing the speed and direction in which light travels, the scientists can guide light waves around a micrometer-sized bump in such a way as to render it invisible in three dimensions, and at wavelengths of light close to those visible to humans. Work is underway to extend the effect into the visible range and the results are expected in January.
Until now, such ‘invisibility cloaks’ have only worked in two dimensions. This meant that the concealed object was invisible when the observer attempted to look at it head on, but became visible when viewed from the side. This study is the first to result in the creation of a device that renders an object invisible in all three dimensions.
Future applications of this research could lie in the development of entirely new optical components, such as perfect lenses, light storage devices, and important components for lasers and optoelectronics such as modulators and isolators. While full-body invisibility cloaks remain beyond the reach of current science and technology, this research has proved an important principle that was until recently believed to be impossible.