Sensitivity to hole doping of CuL3resonant spectroscopies: Inelastic x-ray scattering and photoemission ofLa2−xSrxCuO4

Abstract

We present Cu ${L}_{3}$ edge resonant inelastic x-ray scattering (RIXS) and resonant x-ray photoemission spectroscopy (RXPS) of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Cu}{\mathrm{O}}_{4}$ ($x=0.0$, 0.13, and 0.27). RIXS is found to be much more sensitive to the hole doping level than resonant photoemission. RIXS allows us to determine the average energy of $dd$ excitations of both undoped and hole doped sites. The trade-off between the Raman and non-Raman spectral features depends on the doping level strongly in RIXS but weakly in RXPS. These experimental findings are consistently interpreted within a cluster model: The role of nonlocal core hole screening in the intermediate state is shown to be crucial. Nonlocal screening has an impact also on the interpretation of the ${L}_{3}$ x-ray absorption spectra in cuprates.