Southampton, England--Researchers at the University of Southampton's Optoelectronics Research Centre (ORC) have created a metamaterial with optical properties that can be controlled by electric signals.1
The metamaterial contains nanoscale parts, called plasmonic metamolecules, that are supported by nanosized strings of silicon nitride. Applying an electric field of a few volts allows the strings to be driven in sync at megahertz frequencies; the result is a reconfiguration of the metamolecules, which changes the transmission and reflection spectra of the metamaterial.
"We have found a fast and reliable way of coordinating the motion of thousands of metamaterial building blocks," says Eric Plum, Research Lecturer at the ORC. "We shift them by distances smaller than the diameter of a human hair. These minute rearrangements are sufficient to radically change the transmission and reflection characteristics of the metamaterial. We do this by engaging the same force that sticks a small piece of paper to a comb after brushing. In essence, we dictate the movement of metamaterial building blocks with electrical signals, and we can do this very fast."
Metamaterials research has grown rapidly in the past decade. The University's Centre for Photonic Metamaterials is supported by the Engineering and Physical Sciences Research Council and is at the forefront of this development.
REFERENCE:
1. J. Y. Ou et al., Nature Nanotechnology (2013) http://dx.doi.org/10.1038/NNANO.2013.25
