Chemical and Magnetic Imaging with X-Ray Photoemission Electron Microscopy

Abstract

X-ray photoemission electron microscopy (XPEEM) is a full-field imaging technique giving access to the chemical state and magnetic order of laterally inhomogeneous surfaces, interfaces and thin films. In its simplest variant, synchrotron-based PEEM uses secondary emission to map local differences in the oxidation state, valence, and bond orientation around the emitter. The combination with X-ray circular and linear dichroism techniques represents the most frequent application, and has found extensive use in imaging ferromagnetic and antiferromagnetic domains. XPEEM instruments with energy filter can implement laterally resolved X-ray photoelectron spectroscopy (XPS) and angle resolved photoelectron spectroscopy (ARPES), reaching high chemical and electronic structure sensitivity. Here, we describe the basic aspects and methods of synchrotron-based spectromicroscopy with the PEEM, and its combination with low energy electron microscopy (LEEM). The present state of the art of the technique will be illustrated by applications in diverse fields, spanning from surface and materials sciences to biology and magnetism.