Evidence for the half-metallic ferromagnetic state ofFe3O4by spin-resolved photoelectron spectroscopy

The spin-dependent electronic structure of thin epitaxial films of magnetite, ${\mathrm{Fe}}_{3}{\mathrm{O}}_{4}(111),$ has been investigated at room temperature by means of spin-, energy-, and angle-resolved photoemission spectroscopy. Near the Fermi energy ${E}_{F}$ a spin polarization of $\ensuremath{-}(80\ifmmode\pm\else\textpm\fi{}5)%$ is found. The spin-resolved photoemission spectra for binding energies between 1.5 eV and ${E}_{F}$ show good agreement with spin-split band energies from density-functional calculations.