Resonant Inelastic X-Ray Scattering from Valence Excitations in Insulating Copper-Oxides
arXiv:cond-mat/9810095 · doi:10.1103/PhysRevLett.83.860
Abstract
We report resonant inelastic x-ray measurements of insulating La$_2$CuO$_4$ and Sr$_2$CuO$_2$Cl$_2$ taken with the incident energy tuned near the Cu K absorption edge. We show that the spectra are well described in a shakeup picture in 3rd order perturbation theory which exhibits both incoming and outgoing resonances, and demonstrate how to extract a spectral function from the raw data. We conclude by showing {\bf q}-dependent measurements of the charge transfer gap.
minor notational changes, discussion of anderson impurity model fixed, references added; accepted by PRL