摘要
Based on the underlying graphene lattice symmetry and an itinerant magnetism model on a bipartite lattice,we propose a unifi ed geometric rule for designing graphene-based magnetic nanostructures:spins are parallel(ferromagnetic(FM))on all zigzag edges which are at angles of 0°and 120°to each other,and antiparallel(antiferromagnetic(AF))at angles of 60°and 180°.The rule is found to be consistent with all the systems that have been studied so far.Applying the rule,we predict several novel graphene-based magnetic nanostructures:0-D FM nanodots with the highest possible magnetic moments,1-D FM nanoribbons,and 2-D magnetic superlattices.
基金
The work at Utah is supported by DOE
the work at IOP is supported by NSFC
the work at UoW is supported by the Australian Research Council(ARC)Discovery grant
Liu also acknowledges support by an ARC international professorial fellowship and Dr.X.L.Wang for helping to prepare the figures.First principles calculations were performed on computers at DOE-NERSC and CHPC of University of Utah.