PROBLEM: Metamaterials, a new class of artificial materials that can affect light in ways not possible in nature, open the door to things like real-life invisibility cloaks and computers that use photons instead of electrons. But current metamaterials absorb or scatter too much light to make such devices practical.
SOLUTION: Alexandra Boltasseva, a professor of electrical and computer engineering at Purdue University, is replacing the metals normally used in metamaterials with semiconductors, such as zinc oxide, that have been doped with aluminum or gallium. Doping the semiconductor makes it behave more like the metals used in metamaterials, but without the associated optical losses. Currently, these doped semiconductors are suitable for manipulating infrared light, and Boltasseva is working on developing formulations that will work with visible light. Another advantage of these materials is that their properties can be altered by applying an electric field, which would make them suitable for applications such as communications and computing.
“We are talking about a whole new generation of devices that are based on new principles of manipulating light,” she says. —David Talbot