Evidence for Ferromagnetic Order at the FeO(111) Surface

Abstract

By using spin-polarized secondary electron spectroscopy, we have found that the surface of FeO(111) prepared by oxidation of Fe(110) is ferromagnetically ordered above the bulk N\'eel temperature of 198 K. A possible cause of the ordering is the reconstruction of a polar FeO(111) surface to reduce electrostatic surface energy.