Spin and orbital magnetic moment of reconstructed √2 x √2R45°magnetite(001)

The surface of a magnetite single crystal with (001) orientation has been prepared by sputtering/annealing cycles providing the root 2 x root 2R45 degrees reconstruction. The distribution of magnetic domains on the surface has been imaged by x-ray magnetic dichroism in a photoemission microscope. The easy axes are along the surface in-plane < 110 > directions. The near-surface magnetic moment was determined by applying the sum rules to XMCD spectra obtained with different kinetic energies of the secondary electrons. A reduced total moment of 3.3 mu B and a ratio of about 0.10 between orbital and spin moment was found, which we attribute to the surface reconstruction.