Abstract: Magnetite is an iron oxide known as the oldest magnetic material. It is a magnetic conductor (presumed to be a half-metal) with applications in fields as diverse as catalysis and spintronics. It has a metal insulator transition (Verwey transition) at ~120 K which has been the subject of a heated debate that continues today concerning its origin and particular charge order (or lack of). The (100) surface of magnetite is one of the best understood of its compact surfaces. We have been working on magnetite, mostly with low-energy electron microscopy and related techniques, both on thin films and on the surface of bulk crystals, for the last years. In this presentation we will focus on our recent results on the transitions observed on the (100) surface of bulk magnetite crystals and their temperature evolution. We will show a variety of low-energy electron techniques to image the magnetic domains using spin-polarized low-energy electron for illumination, x-ray magnetic circular dichroism photoemission and spin-resolved photoemission.
Instituto de Química Física “Rocasolano” CSIC, Madrid, Spain