title: Ir(111) surface state with giant Rashba splitting persists under graphene in air.
abstract: We reveal a giant Rashba effect (α(R)≈1.3  eV Å) on a surface state of Ir(111) by angle-resolved photoemission and by density functional theory. It is demonstrated that the existence of the surface state, its spin polarization, and the size of its Rashba-type spin-orbit splitting remain unaffected when Ir is covered with graphene. The graphene protection is, in turn, sufficient for the spin-split surface state to survive in ambient atmosphere. We discuss this result along with indications for a topological protection of the surface state.
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Elektronenspeicherring BESSY II, Berlin, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Varykhalov
authors.forename: D
authors.initials: D
authors.lastname: Marchenko
authors.forename: M R
authors.initials: MR
authors.lastname: Scholz
authors.forename: E D L
authors.initials: ED
authors.lastname: Rienks
authors.forename: T K
authors.initials: TK
authors.lastname: Kim
authors.forename: G
authors.initials: G
authors.lastname: Bihlmayer
authors.forename: J
authors.initials: J
authors.lastname: Sánchez-Barriga
authors.forename: O
authors.initials: O
authors.lastname: Rader