Inelastic x-ray scattering as a probe of electronic correlations

Abstract

We construct an exact dynamical mean field theory for nonresonant inelastic light scattering in the infinite-dimensional Falicov-Kimball model, which can be tuned through a quantum critical metal-insulator transition. Due to the projection of the polarization orientations onto different regions of the Brillouin zone and due to the transfer of energy and momentum from the light to the strongly correlated charge excitations, the nature of the dynamics can be naturally interpreted as strongly temperature-dependent low-energy particle-hole excitations and weakly temperature-dependent high-energy charge transfer excitations which depend delicately on the electronic correlations. These results can be used to give important information concerning the evolution of charge dynamics in different regions of the Brillouin zone.