Electronic structure and spin polarization of theFe(001)−p(1×1)Osurface

Abstract

We present a combined experimental and theoretical study on electronic and magnetic properties of the $\text{Fe}(001)\text{\ensuremath{-}}p(1\ifmmode\times\else\texttimes\fi{}1)\text{O}$ surface. The ordered $p(1\ifmmode\times\else\texttimes\fi{}1)$ surface is investigated with spin-polarized scanning tunneling microscopy and spectroscopy accompanied by first-principles calculations. The atomic registry of the $\text{Fe}(001)\text{\ensuremath{-}}p(1\ifmmode\times\else\texttimes\fi{}1)\text{O}$ surface was confirmed in real space from the atomically resolved images. Tunneling spectroscopy reveals two oxygen induced features in the local density of states, around $\ensuremath{-}0.7\text{ }\text{eV}$ and at the Fermi level, the origin of which is discussed based on first-principles calculations. Due to the hybridization of oxygen ${p}_{z}$ states with the Fe states near the Fermi level, the spin polarization in tunneling experiments is inverted upon oxygen adsorption.