Polarization dependence of core-level X-ray photoemission spectra in anisotropic solids

Abstract

A theoretical prediction of polarization-dependent XPS in anisotropic solids is given, with Cu 2 p- and 3 p- XPS in La 2CuO 4 as an example. The XPS due to the dipole p → s transition is shown to exhibit an appreciable polarization dependence, which originates from the multiplet-coupling between the core hole and anisotropic Cu 3 d electrons. The polarization-dependent 3 p → ε s process can be made to dominate an almost polarization-independent 3 p → ε d process by tuning the incident photon energy to the Cooper minimum of the 3 p → ε p transition at about 22 eV above the threshold.