Non-equilibrium spin accumulation in ferromagnetic single-electron transistors

Arne Brataas, Yu. V. Nazarov, J. Inoue, G. E. W. Bauer

Published 1998-12-14Version 1

We study transport in ferromagnetic single-electron transistors. The non- equilibrium spin accumulation on the island caused by a finite current through the system is described by a generalized theory of the Coulomb blockade. It enhances the tunnel magnetoresistance and has a drastic effect on the time- dependent transport properties. A transient decay of the spin accumulation may reverse the electric current on time scales of the order of the spin-flip relaxation time. This can be used as an experimental signature of the non- equilibrium spin accumulation.