title: Resonant inelastic X-ray scattering of the holon-antiholon continuum in SrCuO2.
abstract: We report a resonant inelastic x-ray scattering study of charge excitations in the quasi-one-dimensional Mott insulator SrCuO2. We observe a continuum of low-energy excitations, the onset of which exhibits a small dispersion of approximately 0.4 eV. Within this continuum, a highly dispersive feature with a large sinusoidal dispersion (approximately 1.1 eV) is observed. We have also measured the optical conductivity, and studied the dynamic response of the extended Hubbard model with realistic parameters, using a dynamical density-matrix renormalization group method. In contrast to earlier work, we do not find a long-lived exciton, but rather these results suggest that the excitation spectrum comprises a holon-antiholon continuum together with a broad resonance.
authors.affiliation: Department of Physics, Brookhaven National Laboratory, Upton, New York 11973, USA.
authors.forename: Young-June
authors.initials: YJ
authors.lastname: Kim
authors.forename: J P
authors.initials: JP
authors.lastname: Hill
authors.forename: H
authors.initials: H
authors.lastname: Benthien
authors.forename: F H L
authors.initials: FH
authors.lastname: Essler
authors.forename: E
authors.initials: E
authors.lastname: Jeckelmann
authors.forename: H S
authors.initials: HS
authors.lastname: Choi
authors.forename: T W
authors.initials: TW
authors.lastname: Noh
authors.forename: N
authors.initials: N
authors.lastname: Motoyama
authors.forename: K M
authors.initials: KM
authors.lastname: Kojima
authors.forename: S
authors.initials: S
authors.lastname: Uchida
authors.forename: D
authors.initials: D
authors.lastname: Casa
authors.forename: T
authors.initials: T
authors.lastname: Gog