Graphene transistor, artwork. The transistor consists of a graphene bilayer (black net) over a silica (silicon oxide) insulator (blue) that is sitting on a silicon bottom gate (yellow). A gold source (gold, left) and a gold drain (gold, right) sit on the graphene at either end and a platimum top gate (grey, centre) sits on its centre. Graphene, a single layer of graphite, is composed of carbon atoms arranged in a honeycomb crystal lattice. It transports electrons highly efficiently and may one day replace silicon in computer chips and other technology applications.