Modulating doping and interface magnetism of epitaxial graphene on SiC(0001)

On the basis of first principles calculations, we report that the type and density of charge carriers of epitaxial graphene on Si C(0001) can be deliberately controlled by decorating the buffer layer with specific atoms(i.e., F, Cl, O, or N). More importantly, a fine tuning of the doping behavior from intrinsic n-type to charge neutrality to p-type and interface magnetism is achieved via increasing the doping concentration of F atoms on the buffer layer. Our results suggest an interesting avenue to the application of epitaxial graphene in nanoscale electronic and spintronic devices.