  We have grown high-quality magnetite micrometric islands on ruthenium stripes
on sapphire through a combination of magnetron sputtering (Ru film),
high-temperature molecular beam epitaxy (oxide islands), and optical
lithography. The samples have been characterized by atomic force microscopy,
Raman spectroscopy, X-ray absorption and magnetic circular dichroism in a
photoemission microscope. The magnetic domains on the magnetite islands can be
modified by the application of current pulses through the Ru stripes in
combination with magnetic fields. The modification of the magnetic domains is
explained by the Oersted field generated by the electrical current flowing
through the stripes underneath the magnetite nanostructures. The fabrication
method is applicable to a wide variety of rock salt and spinel oxides.
