Fe3O4(111)/Fe(110)magnetic bilayer: Electronic and magnetic properties at the surface and interface

Abstract

The surface and interface properties of the magnetic bilayer ${\mathrm{Fe}}_{3}{\mathrm{O}}_{4}(111)/\mathrm{F}\mathrm{e}(110)$ have been studied by low-energy electron diffraction, spin-polarized photoemission spectroscopy, and magnetic linear dichroism. The electronic structure at the surface region of the oxide departs considerably from the one of the underlying bulk layer. Correspondingly, the surface spin polarization is found to be lower than expected for pure ${\mathrm{Fe}}_{3}{\mathrm{O}}_{4}.$ The magnetic bilayer coupling is driven by the formation of a specific ${\mathrm{Fe}}_{3}{\mathrm{O}}_{4}(111)/\mathrm{F}\mathrm{e}(110)$ interface. The same interface is also formed when an Fe metal overlayer is deposited on the oxide surface.