First, it was the soccer-ball-shaped molecules dubbed buckyballs. Then it was the cylindrically shaped nanotubes. Now, the hottest new material in physics and nanotechnology is graphene: a remarkably flat molecule made of carbon atoms arranged in hexagonal rings much like molecular chicken wire.
Not only is this the thinnest material possible, but it also is 10 times stronger than steel and it conducts electricity better than any other known material at room temperature. These and graphene's other exotic properties have attracted the interest of physicists, who want to study them, and nanotechnologists, who want to exploit them to make novel electrical and mechanical devices.
"There are two features that make graphene exceptional," says Kirill Bolotin, who has just joined the Vanderbilt Department of Physics and Astronomy as an assistant professor. "First, its molecular structure is so resistant to defects that researchers have had to hand-make them to study what effects they have. Second, the electrons that carry electrical charge travel much faster and generally behave as if they have far less mass than they do in ordinary metals or superconductors."
Bolotin has been directly involved in the efforts to manufacture and characterize this exotic new material as a post-doctoral fellow in the laboratory of Philip Kim at Columbia University. In a paper published last week in the journal Nature, he and his Columbia colleagues report that they have managed to clean up graphene enough so that it exhibits a bizarre electrical phenomenon called the fractional quantum Hall effect, where the electrons act together to create new particles with electrical charges that are a fraction that of individual electrons.
Although graphene is the first truly two-dimensional crystalline material that has been discovered, over the years scientists have put considerable thought into how two-dimensional gases and solids should behave. They
|Contact: David F. Salisbury|