title: Sublattice Interference as the Origin of σ Band Kinks in Graphene.
abstract: Kinks near the Fermi level observed in angle-resolved photoemission spectroscopy (ARPES) have been widely accepted to represent electronic coupling to collective excitations, but kinks at higher energies have eluded a unified description. We identify the mechanism leading to such kink features by means of ARPES and tight-binding band calculations on σ bands of graphene, where anomalous kinks at energies as high as ∼4  eV were reported recently [Phys. Rev. Lett. 111, 216806 (2013)]. We found that two σ bands show a strong intensity modulation with abruptly vanishing intensity near the kink features, which is due to sublattice interference. The interference induced local singularity in the matrix element is a critical factor that gives rise to apparent kink features, as confirmed by our spectral simulations without involving any coupling to collective excitations.
authors.affiliation: Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.|Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Sung Won
authors.initials: SW
authors.lastname: Jung
authors.affiliation: Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.|Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Woo Jong
authors.initials: WJ
authors.lastname: Shin
authors.affiliation: Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.|Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Jimin
authors.initials: J
authors.lastname: Kim
authors.affiliation: Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.|Advanced Light Source, E. O. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Luca
authors.initials: L
authors.lastname: Moreschini
authors.affiliation: Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.|Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Han Woong
authors.initials: HW
authors.lastname: Yeom
authors.affiliation: Advanced Light Source, E. O. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Eli
authors.initials: E
authors.lastname: Rotenberg
authors.affiliation: Advanced Light Source, E. O. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Bostwick
authors.affiliation: Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science, Pohang 37673, Korea.|Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Keun Su
authors.initials: KS
authors.lastname: Kim