We consider current-induced domain wall motion and, the reciprocal process, moving domain wall-induced current. The associated Onsager coefficients are expressed in terms of scattering matrices. Uncommonly, in (Ga,Mn)As, the effective Gilbert damping coefficient αw and the effective out-of-plane spin transfer torque parameter βw are dominated by spin-orbit interaction in combination with scattering off the domain wall, and not scattering off extrinsic impurities. Numerical calculations give αw∼0.01 and βw∼1 in dirty (Ga,Mn)As. The extraordinary large βw parameter allows experimental detection of current or voltage induced by domain wall motion in (Ga,Mn)As.
@article{arxiv.0811.2235,
title = {Intrinsic Coupling between Current and Domain Wall Motion in (Ga,Mn)As},
author = {Kjetil M. D Hals and Anh Kiet Nguyen and Arne Brataas},
journal= {arXiv preprint arXiv:0811.2235},
year = {2009}
}