Physicists have created the first ever superconducting graphene sample by coating it with lithium atoms, an advance that may lead to the development of graphene electronics and nanoscale quantum devices.
Although superconductivity has already been observed in intercalated bulk graphite - three-dimensional crystals layered with alkali metal atoms, based on the graphite used in pencils - inducing superconductivity in single-layer graphene has until now eluded scientists.
"This first experimental realisation of superconductivity in graphene promises to usher us in a new era of graphene electronics and nanoscale quantum devices," said Andrea Damascelli, director of University of British Columbia's Quantum Matter Institute.
Graphene, roughly 200 times stronger than steel by weight, is a single layer of carbon atoms arranged in a honeycomb pattern.
Along with studying its extreme physical properties, scientists eventually hope to make very fast transistors, semiconductors, sensors and transparent electrodes using graphene.
"This is an amazing material," said Bart Ludbrook, a former PhD researcher in Damascelli's group at UBC.
"Decorating monolayer graphene with a layer of lithium atoms enhances the graphene's electron-phonon coupling to the point where superconductivity can be stabilised," he said.
Given the massive scientific and technological interest, the ability to induce superconductivity in single-layer graphene promises to have significant cross-disciplinary impacts.
The research team, which included colleagues at the Max Planck Institute for Solid State Research through the joint Max-Planck-UBC Centre for Quantum Materials, prepared the Li-decorated graphene in ultra-high vacuum conditions and at ultra-low temperatures.
The research was published in the Proceedings of the National Academy of Sciences.
