title: Long- versus Short-Range Scattering in Doped Epitaxial Graphene.
abstract: Tuning the electronic properties of graphene by adatom deposition unavoidably introduces disorder into the system, which directly affects the single-particle excitations and electrodynamics. Using angle-resolved photoemission spectroscopy (ARPES) we trace the evolution of disorder in graphene by thallium adatom deposition and probe its effect on the electronic structure. We show that the signatures of quasiparticle scattering in the photoemission spectral function can be used to identify thallium adatoms, although charged, as efficient short-range scattering centers. Employing a self-energy model for short-range scattering, we are able to extract a δ-like scattering potential δ = -3.2 ± 1 eV. Therefore, isolated charged scattering centers do not necessarily act just as good long-range (Coulomb) scatterers but can also act as efficient short-range (δ-like) scatterers; in the case of thallium, this happens with almost equal contributions from both mechanisms.
authors.affiliation: †Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Straßer
authors.affiliation: §Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: B M
authors.initials: BM
authors.lastname: Ludbrook
authors.affiliation: §Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Levy
authors.affiliation: §Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: A J
authors.initials: AJ
authors.lastname: Macdonald
authors.affiliation: §Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.|∥Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
authors.forename: S A
authors.initials: SA
authors.lastname: Burke
authors.affiliation: ⊥Institut für Theoretische Physik, Universität Bremen, 28359 Bremen, Germany.
authors.forename: T O
authors.initials: TO
authors.lastname: Wehling
authors.affiliation: †Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany.|#Institut de Physique de la Matière Condensée, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
authors.forename: K
authors.initials: K
authors.lastname: Kern
authors.affiliation: §Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Damascelli
authors.affiliation: †Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany.
authors.forename: C R
authors.initials: CR
authors.lastname: Ast
keywords: Graphene; angular resolved photoemission spectroscopy; long-range (Coulomb) scattering; self-energy; short-range scattering