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arXiv · 0708.3534

Momentum-resolved charge excitations in high-Tc cuprates studied by resonant inelastic x-ray scattering

K. Ishii·M. Hoesch·T. Inami·K. Kuzushita·K. Ohwada·M. Tsubota·Y. Murakami·J. Mizuki·Y. Endoh·K. Tsutsui·T. Tohyama·S. Maekawa·K. Yamada·T. Masui·S. Tajima·H. Kawashima·J. Akimitsu
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Abstract

We report a Cu K-edge resonant inelastic x-ray scattering (RIXS) study of high-Tc cuprates. Momentum-resolved charge excitations in the CuO2 plane are examined from parent Mott insulators to carrier-doped superconductors. The Mott gap excitation in undoped insulators is found to commonly show a larger dispersion along the [pi,pi] direction than the [pi,0] direction. On the other hand, the resonance condition displays material dependence. Upon hole doping, the dispersion of the Mott gap excitation becomes weaker and an intraband excitation appears as a continuum intensity below the gap at the same time. In the case of electron doping, the Mott gap excitation is prominent at the zone center and a dispersive intraband excitation is observed at finite momentum transfer.

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K. Ishii, M. Hoesch, T. Inami, K. Kuzushita, K. Ohwada, M. Tsubota, Y. Murakami, J. Mizuki, Y. Endoh, K. Tsutsui, T. Tohyama, S. Maekawa, K. Yamada, T. Masui, S. Tajima, H. Kawashima, J. Akimitsu. 2007-08-27. Momentum-resolved charge excitations in high-Tc cuprates studied by resonant inelastic x-ray scattering. https://doi.org/10.1016/j.jpcs.2008.06.041

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