Inducing large ferromagnetic ordering in graphite by 1 MeV 12C+ ion irradiation

1 MeV 12C+ ions are bombarded on highly oriented pyrolytic graphite (HOPG) samples in order to study the induced magnetic-ordering in graphite due to ion–matter interactions. Large but slightly different ferromagnetic moments are observed in the in-plane and in the out-of-plane orientations of the HOPG flake on irradiating with mild doses of few pC/μm2 range. The magnetic moment observed under optimal irradiation parameters is found to be at least two orders of magnitude higher than that reported earlier for HOPG in any of the MeV-range ion-irradiation experiments. 1 MeV 12C+ ions are thus capable of creating favorable condition for magnetic order more effectively than other bombarding ions studied so far. At larger fluences, the crystal structure gets more damaged and the magnetic moment sharply decreases.