Spin‐Polarized Low‐Energy Electron Microscopy (SPLEEM)

Abstract

AbstractElectron microscopy techniques generally rely on controlling and measuring momentum and energy of electrons scattered at a sample. Spin‐polarized low energy electron microscopy (SPLEEM) introduces an additional physical dimension by allowing control of the spin‐polarization of the electron beam. The experimental setup is largely identical to low energy electron microscopy (LEEM), the key difference being that a spin‐polarized electron source is used in SPLEEM instead of an unpolarized electron source. In addition to the image contrast mechanisms that are available in LEEM, spin‐spin coupling of illumination electrons with electrons in the sample generates new contrast mechanisms that permit imaging of magnetic properties and phenomena. The electron energies that are most useful for SPLEEM imaging are often in the range of 0 to 30eV and SPLEEM is therefore as surface‐sensitive as LEEM.In the following we will assume that the reader is familiar with the basic concepts of LEEM or refers to the Low‐ Energy Electron Microscopy article for reference. This article details the basic mechanism for spin resolved contrast and the design of the spin gun and spin manipulator. An overview of some of the capabilities of SPLEEM is given in the applications section where some recent experiments are reviewed.