Washington, June 9 : New studies have determined that graphene's promising electronic properties will make it the ideal material for the development of next generation communication devices and nanoscale electronics.
Graphene is the two-dimensional crystalline form of carbon: a single layer of carbon atoms arranged in hexagons, and was discovered by physicists at the University of Manchester in 2004.
Now, researchers at the Department of Energy's Advanced Light Source (ALS), from DOE's Lawrence Berkeley National Laboratory and the University of California at San Diego (UCSD), have measured the extraordinary properties of graphene with an accuracy never before achieved.
The results confirm many of the strangest features of the unusual material, but also reveal significant departures from theoretical predictions. They point the way to novel practical applications, such as tunable optical modulators for communications and other nanoscale electronics.
The studies were performed by Zhiqiang Li, an ALS Doctoral Fellow from Dimitri Basov's laboratory at UCSD, working with colleagues at Columbia University in New York and the National High Magnetic Field Laboratory in Florida, and with Berkeley Lab's Michael Martin.
"Graphene's unusual electronic properties arise from the fact that the carbon atom has four electrons, three of which are tied up in bonding with its neighbors," said Li.
"But the unbound fourth electrons are in orbitals extending vertically above and below the plane, and the hybridization of these spreads across the whole graphene sheet," he added.
According to Li, the electrons in graphene are "sort of free".
Unlike electrons in other materials, the electrons in graphene move ballistically - without collisions - over great distances, even at room temperature.
As a result, the ability of the electrons in graphene to conduct electrical current is 10 to 100 times greater than those in a normal semiconductor like silicon at room temperature.
This makes graphene a very promising candidate for future electronic applications.