title: Spin-induced band modifications of graphene through intercalation of magnetic iron atoms.
abstract: Intercalation of magnetic iron atoms through graphene formed on the SiC(0001) surface is found to induce significant changes in the electronic properties of graphene due mainly to the Fe-induced asymmetries in charge as well as spin distribution. From our synchrotron-based photoelectron spectroscopy data together with ab initio calculations, we observe that the Fe-induced charge asymmetry results in the formation of a quasi-free-standing bilayer graphene while the spin asymmetry drives multiple spin-split bands. We find that Fe adatoms are best intercalated upon annealing at 600 °C, exhibiting split linear π-bands, characteristic of a bilayer graphene, but much diffused. Subsequent changes in the C 1s, Si 2p, and Fe 3p core levels are consistently described in terms of Fe-intercalation. Our calculations together with a spin-dependent tight binding model ascribe the diffuse nature of the π-bands to the multiple spin-split bands originated from the spin-injected carbon atoms residing only in the lower graphene layer.
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang, Korea. jwc@postech.ac.kr.
authors.forename: S J
authors.initials: SJ
authors.lastname: Sung
authors.forename: J W
authors.initials: JW
authors.lastname: Yang
authors.forename: P R
authors.initials: PR
authors.lastname: Lee
authors.forename: J G
authors.initials: JG
authors.lastname: Kim
authors.forename: M T
authors.initials: MT
authors.lastname: Ryu
authors.forename: H M
authors.initials: HM
authors.lastname: Park
authors.forename: G
authors.initials: G
authors.lastname: Lee
authors.forename: C C
authors.initials: CC
authors.lastname: Hwang
authors.forename: Kwang S
authors.initials: KS
authors.lastname: Kim
authors.forename: J S
authors.initials: JS
authors.lastname: Kim
authors.forename: J W
authors.initials: JW
authors.lastname: Chung
mesh_terms: D006108:Graphite / Q000737:chemistry*; D007364:Intercalating Agents / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008280:Magnetics; D011789:Quantum Theory; D013499:Surface Properties
chemical_list: D007364:Intercalating Agents; D006108:Graphite; D007501:Iron