Shape of things to comeImperial College London awarded £4.9 million to research cloaking properties of metamaterials

The Leverhulme Trust has awarded Imperial College London £4.9 million in funding to investigate new applications for metamaterials that can bend, control and manipulate light and electromagnetic waves.

Metamaterials are said to have properties that could lead to the development of invisibility “cloaking” devices, sensitive security sensors, and flat lenses that can be used to image objects much smaller than the wavelength of light (see “‘Active Cloak’ Protects Buildings from Earthquakes,” 17 August 2009 HSNW; and “Active Cloaking Offers an Alternative to Metamaterials,” 24 August 2009 HSNW).

The project team will be led by Imperial’s Sir John Pendry, who first proposed that metamaterials could be used to build an invisibility cloak in 2006, and Professor Stefan Maier, a leading experimentalist in the field of plasmonics. Also collaborating in the project is Professor Nikolay Zheludev’s team at Southampton University.

Sir John said that the grant will help British universities to develop real-world metamaterial applications based on his theories, including the optical invisibility cloak, which would render an object invisible to the human eye. “We’ve shown that an optical invisibility cloak is theoretically possible: the big challenge now is to build it,” he said.
Metamaterials have a carefully designed an internal structure that interacts with light and other electromagnetic waves in unique ways, producing effects not seen in nature. Scientists can design them so that they control the movement and direction of all kinds of radiation — from visible light to microwaves and terahertz radiation.

Being able to control radiation using materials in this way is a relatively new scientific development and opens up a realm of potential applications in diverse fields, including medicine, security, imaging, telecommunications and data processing.

In imaging, metamaterials could be used to build a “perfect lens” microscope that would enable scientists to look at objects smaller than the wavelength of light being used.
In security technology, airport scanners could use T-ray radiation to detect very small quantities of poisons and explosives, and advances in metamaterials could make them work.

Professor Maier from Imperial’s Department of Physics, co-leader of the project, said: “With metamaterials, we can devise completely new ways of controlling radiation, from visible light all the way down to terahertz radiation and beyond. What we are aiming at are structures that are easy to make but that can give us a level of control over the flow of radiation thought impossible until now. For example, we can make surfaces that guide terahertz or even radiofrequency waves along them, with their energy highly concentrated right there at the surface, extending only a tiny fraction of the wavelength away from it. This might greatly improve the sensitivity of terahertz sensing devices and allow new ways to harness low-frequency radiation.”

The Imperial College London and Southampton University research teams will also be focusing on developing metamaterials for use in energy harvesting, optoelectronics, fiber optics, bionanotechnology and imaging.