14 DAY TRIAL // Since its discovery 6 years ago, graphene has been under intensive research because of the weird properties theory holds it should have. Now, new investigations are revealing that the material may in fact be even stranger than first hypothesized.
For instance, experiments conducted at the Advanced Light Source (ALS) show that the carbon compound is a very special material. Not only does it have unusual chemical and physical properties, but it can also display behaviors that experts had no idea were possible.
Graphene is made up of pure carbon. Atoms are arranged in a hexagonal, honeycomb-like formation, which provides the chemical with extreme strength and durability. The flow of electrons through it is also very unconventional, physicists say.
The kick about graphene is that it has only two dimensions. It is only one atom thick, so experts most often refer to it as being 2D. The compound is harder than diamonds, and holds great promise for replacing silicon as our civilization's primary raw material for electronic devices.
In the latest study on the material, experts at the US Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab), in California, gained a deeper insight into the very nature of graphene,
Using the ALS, the group found that “graphene is not a semiconductor, not an insulator, and not a metal,” lead study author David Siegel explains. The work is detailed in the latest issue of the esteemed journal Proceedings of the National Academy of Sciences (PNAS).
“It’s a special kind of semimetal, with electronic properties that are even more interesting than one might suspect at first glance,” adds the scientist, who is a graduate student at the Berkeley Lab Materials Sciences Division (MSD).
He is also a member of the Alessandra Lanzara research group, at the University of California in Berkeley's (UCB) Department of Physics. The expert and his team conducted their research on undoped graphene, meaning that the material had no extra charge carriers.
“Since the properties of so many materials are pretty much the same in a generalized way, physicists are always interested in finding systems that differ from a normal Fermi liquid,” Siegel says.
“This is what makes our results so exciting. Undoped graphene really does differ from what we expect for a normal Fermi liquid, and our results are in good agreement with theoretical calculations,” he adds.