Absorption spectroscopy and XMCD at the Verwey transition of Fe3O4

Fe3O4 has been investigated since decades, because of its magnetic and unusual electronic transport properties, which exhibit significant changes at the so-called Verwey transition, despite the promising high-spin polarization at the Fermi energy. We will show detailed and angular-dependent magnetic (XMCD) and nonmagnetic (XAS) absorption spectroscopy results of a high-quality single crystal, comparing cleaved and polished surfaces from the same single crystal. While the cleaved sample exhibits the full spin moment of magnetite, the same sample with a polished surface exhibits a magnetic moment reduced by a factor of 2, indicating a reduced surface magnetization. Angular-dependent XMCD measurements do not exhibit any significant variation. These results are consistent to recently published photoemission data