  Density-functional calculations are performed to explore magnetoelectric
effects originating from the influence of an external electric field on
magnetic properties of the Fe/MgO(001) interface. It is shown that the effect
on the interface magnetization and magnetocrystalline anisotropy can be
substantially enhanced if the electric field is applied across a dielectric
material with a large dielectric constant. In particular, we predict an
enhancement of the interface magnetoelectric susceptibility by a factor of the
dielectric constant of MgO over that of the free standing Fe (001) surface. We
also predict a significant effect of electric field on the interface
magnetocrystalline anisotropy due to the change in the relative occupancy of
the 3d-orbitals of Fe atoms at the Fe/MgO interface. These results may be
interesting for technological applications such as electrically controlled
magnetic data storage.
