Oxygen on Fe(100): An Initial-Oxidation Study by Spin-Polarized Auger Spectroscopy

Spin-polarized Auger spectroscopy is applied to a study of initial oxidation of Fe(100). The O $\mathrm{KLL}$ lines are found to exhibit positive (i.e., parallel to the Fe magnetization) spin polarization for the singlet and near zero or negative spin polarization for the triplet final states. The finding is relevant for an experimental determination of orbital mixing coefficients. True secondary electrons reveal strongly spin-polarized O-induced structures at 3 and 12 eV above the vacuum level.