Electrons in graphene 'have no mass'

Their work, published in Science, is said to help to explain the unusual physical phenomena and properties associated with graphene, which is formed of a single layer of carbon atoms. Graphene is being examined as a potential material for next generation electronic devices. Electrons in graphene are more than 100 times more mobile than those in silicon, prompting researchers to consider the possibility that graphene might replace silicon as the basis for integrated circuits. The research team believes this increased mobility is due to electrons and other carriers of electric charges in graphene behaving as though they have no mass. 'Although they do not approach the speed of light, the unbound electrons in graphene behave much like photons, massless particles of light that also move at a speed independent of their energy', the researchers note. A special NIST instrument was used to zoom in on the graphene layer, tracking the electronic states while applying high magnetic fields. This allowed a high resolution map of the distribution of energy levels in graphene to be created. This showed that, in contrast to metals and other conducting materials, the distance from one energy peak to the next is uneven in graphene. The work is thought to show a way to developing manufacturing methods for making large, uniform batches of graphene for carbon based electronics. Photo credit: Kubista, Georgia Institute of Technology