Dynamical screening in SrVO3: Inelastic x-ray scattering experiments and ab initio calculations

We characterize experimentally and theoretically the high-energy dielectric screening properties of the prototypical correlated metal SrVO3. The dynamical structure factor measured by inelastic x-ray scattering spectroscopy as a function of momentum transfer is in very good agreement with first-principles calculations in the adiabatic local-density approximation to time-dependent density-functional theory. Our results reveal the crucial importance of crystal local fields in the charge response function of correlated materials: They lead to depolarization effects for localized excitations and couple spectra from different Brillouin zones.