Electron interaction on the giant magnetoresistance in the perpendicular geometry

We discuss the effect of electron interaction on the giant magnetoresistance in the perpendicular geometry. Spin accumulation induces a dipole layer of charge at the interface of a magnitude proportional to the current. This layer of interface charge is self-consistently screened. As a result both the magnetoresistance and the spin decay length are dramatically changed. This change is greater for a larger difference between the spin-up and the spin-down bands.