Acoustic plasmons and doping evolution of Mott physics in resonant inelastic x-ray scattering from cuprate superconductors

By incorporating a long-range Coulomb interaction into the framework of the one-band Hubbard model, they delineate how the low-energy plasmon around 1 eV, which is a universal feature of the charge dynamics of the cuprates, manifests itself in the resonant inelastic x-ray scattering (RIXS) spectra. The long-range Coulomb interaction in the doped system control sthe form of the intraband RIXS dispersion near the Brillouin zone center around the {Gamma} point. The out-of-plane momentum transfer component q{sub z} is found to play a key role in determining whether or not the RIXS spectrum shows a plasmon-related gap at {Gamma}.