An NSF Materials Research Science and Engineering Center (MRSEC)

1. Center for Emergent Materials The Ohio State University http://cem.osu.edu Nonmagnetic elements turn graphene magnetic Chris P. Hammel, Ohio State University Research Foundation, DMR 0820414 • Physicists have predicted that graphene, a single atomic sheet of carbon, could be turned magnetic simply by attaching a hydrogen atom (or removing a carbon atom). However, detecting this magnetism has been elusive due to many pitfalls that arise using traditional methods. • Kawakami has developed a new method to detect magnetism in graphene. Pure spin currents are injected into graphene, which then depolarize in a particular and recognizable way if magnetic moments are present. This experiment provides the clearest evidence to date that hydrogen adatoms (or lattice vacancies) generate magnetism in graphene. • In addition to its impact on fundamental physics of magnetism and quantum mechanics, this work also has important ramifications on spin-based electronics for magnetic sensing and advanced computers. Magnetic moments induced by hydrogen atoms attached to the graphene sheet impede the flow of spins, and this reduces the spin current. This effect vanishes when a sufficiently large magnetic field is applied. Co Au Co Roland Kawakami An NSF Materials Research Science and Engineering Center (MRSEC) Supported under Award Number DMR-0820414