Spin polarized inverse photoemission studies of surface magnetism and electronic structure

Abstract

Abstract Spin polarized inverse photoelectron spectroscopy (SPIPES) is shown to be a powerful new technique to study surface and near-surface electronic structure and magnetism. The process, the information obtained, and the apparatus required in a spin polarized inverse photoemission measurement are compared to the complementary spin polarized photoemission measurement. In SPIPES spectra of a clean Ni(110) surface, transitions to the minority spin 3d holes that give rise to ferromagnetism in Ni can be directly observed, as can sp states which are spin slit as an indirect consequence (via s-d hybridization) of the exchange splitting of the d bands. The adsorption of oxygen or carbon monoxide on Ni(110) causes a dramatic decrease in the number of minority 3d holes, that is, in the magnetic moment of the Ni atoms. The data allow us to severely limit the possible models of how chemisorption induces changes in surface magnetism. Other SPIPES studies, such as the temperature dependent behavior of empty bands in ferromagnetic Fe, and future directions and applications of SPIPES will be reviewed.