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Momentum Dependence of Charge Excitations in the Electron-Doped Superconductor Nd1.85Ce0.15CuO4: a RIXS Study

K. Ishii·K. Tsutsui·Y. Endoh·T. Tohyama·S. Maekawa·M. Hoesch·K. Kuzushita·M. Tsubota·T. Inami·J. Mizuki·Y. Murakami·K. Yamada
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Abstract

We report a resonant inelastic x-ray scattering (RIXS) study of charge excitations in the electron-doped high-Tc superconductor Nd1.85Ce0.15CuO4. 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.

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K. Ishii, K. Tsutsui, Y. Endoh, T. Tohyama, S. Maekawa, M. Hoesch, K. Kuzushita, M. Tsubota, T. Inami, J. Mizuki, Y. Murakami, K. Yamada. 2004-12-17. Momentum Dependence of Charge Excitations in the Electron-Doped Superconductor Nd1.85Ce0.15CuO4: a RIXS Study. https://doi.org/10.1103/physrevlett.94.207003

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