Isolation of Exchange- and Spin-Orbit-Driven Effects Via Manipulation of the Axis of Quantization

Double polarization photoelectron spectroscopy using circularly polarized x-rays and true spin detection has been performed using the 2p core levels of ultrathin films of Fe and Co. This includes both the separation into magnetization- and spin-specific spectra and an analysis of the polarization, asymmetry, and related quantities. It is shown how to selectively manipulate the manifestation of exchange- and spin-orbit effects simply by choosing different axes of quantization. Furthermore, the underlying simplicity of the results can be confirmed by comparison to a simple yet powerful single-electron picture.