Electric field control of interface magnetic anisotropy

We present a model for determining the Rashba spin-orbit coupling (RSOC) at magnetic surfaces or interfaces by explicitly taking into account the interaction between the inversion-symmetry-broken potential and the spin-dependent electric dipoles of the Bloch states. We show that the RSOC alone can generate a perpendicular surface magnetic anisotropy comparable to the observed values in transition metals. When an external electric field is applied across the interface, the induced screening potential modifies the RSOC and thus controls the direction of the magnetization. Our results are consistent with the existing experiments.