Physicists find theory on graphene wrong and its conductivity is 10x greater than thought

02/06/2014 - 00:00

By Dexter Johnson - 

An international team of researchers has developed a novel way to produce graphene nanoribbons that enables electrons to travel though it without resistance at room temperature, a property known as ballistic transport. The ballistic transport properties measured by the researchers exceeds previous theoretical limits for graphene by a factor of ten, opening up the potential in the opinion of the researchers for graphene to usher in a new era in electronics despite the material's lack of a band gap. 

The team of researchers, including those at Georgia Institute of Technology along with others from Leibniz Universität Hannover in Germany, the Centre National de la Recherche Scientifique (CNRS) in France and Oak Ridge National Laboratory in the United States, has developed a process for producing graphene nanoribbons on a silicon wafer that results in such high electron mobility that the electrons behave more like photons do when in an optical fiber.

The lack of inherent band gap in graphene—its inability to effectively stop and start the flow of electrons—has remained a major stumbling block in developing it for use in electronics. Of course, there have been various approaches to engineering a band gap into graphene, such as applying a strong electrical field to bilayer graphene. However, Walt de Heer, a Regent's professor in the School of Physics at the Georgia Institute of Technology, believes that we should stop trying to get graphene to behave like silicon, and instead design a new type of electronics that exploits graphene’s unique properties. This is along the lines of what Samsung proposed 18 months agoby developing new switches to exploit graphene’s electron mobility.