Nonexistence of intrinsic spin currents.
We describe the electron spin dynamics in the presence of Rashba spin-orbit interaction and disorder using the spin-density matrix method. We show that in the Born approximation in the scattering amplitude the spin current is zero for an arbitrary ratio of the spin-orbit splitting and the scattering rate. Various types of the disorder potential are studied. We argue that the bulk spin current always depends explicitly on scattering by impurities. In this sense universal intrinsic spin current does not exist.
Physics Department and Center for NanoScience, Ludwig-Maximilians-Universität München, D-80333, Germany.
Alexander
A
Khaetskii