title: Momentum dependence of charge excitations in the electron-doped superconductor Nd1.85 Ce0.15 CuO4: a resonant inelastic x-ray scattering study.
abstract: We report a resonant inelastic x-ray scattering (RIXS) study of charge excitations in the electron-doped high-T(c) superconductor Nd1.85 Ce0.15 CuO4. The intraband and interband excitations across the Fermi energy are separated for the first time by tuning the experimental conditions properly to measure charge excitations at low energy. A dispersion relation with q-dependent width emerges clearly in the intraband excitation, while the intensity of the interband excitation is concentrated around 2 eV near the zone center. The experimental results are consistent with theoretical calculation of the RIXS spectra based on the Hubbard model.
authors.affiliation: Synchrotron Radiation Research Center, Japan Atomic Energy Research Institute, Hyogo 679-5148, Japan. kenji@spring8.or.jp
authors.forename: K
authors.initials: K
authors.lastname: Ishii
authors.forename: K
authors.initials: K
authors.lastname: Tsutsui
authors.forename: Y
authors.initials: Y
authors.lastname: Endoh
authors.forename: T
authors.initials: T
authors.lastname: Tohyama
authors.forename: S
authors.initials: S
authors.lastname: Maekawa
authors.forename: M
authors.initials: M
authors.lastname: Hoesch
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authors.initials: K
authors.lastname: Kuzushita
authors.forename: M
authors.initials: M
authors.lastname: Tsubota
authors.forename: T
authors.initials: T
authors.lastname: Inami
authors.forename: J
authors.initials: J
authors.lastname: Mizuki
authors.forename: Y
authors.initials: Y
authors.lastname: Murakami
authors.forename: K
authors.initials: K
authors.lastname: Yamada