  Magnetic properties of nanometer thick Co films intercalated at the
graphene/Ir(111) interface are investigated using spin-polarized low-energy
electron microscopy (SPLEEM) and Auger electron spectroscopy. We show that the
graphene top layer promotes perpendicular magnetic anisotropy in the Co film
underneath, even for relatively thick intercalated deposits. The magnetic
anisotropy energy is significantly larger for the graphene/Co interface than
for the free Co surface. Hybridization of the graphene and Co electron orbitals
is believed to be at the origin of the observed perpendicular magnetic
anisotropy.
