%0 Journal Article
%T Spin relaxation via exchange with donor impurity-bound electrons
%A Lan Qing
%A Jing Li
%A Ian Appelbaum
%A Hanan Dery
%J Physics
%D 2013
%I arXiv
%R 10.1103/PhysRevB.91.241405
%X At low temperatures, electrons in semiconductors are bound to shallow donor impurity ions, neutralizing their charge in equilibrium. Inelastic scattering of other externally-injected conduction electrons accelerated by electric fields can excite transitions within the manifold of these localized states. Promotion of the bound electron into highly spin-orbit-mixed excited states drives a strong spin relaxation of the conduction electrons via exchange interactions, reminiscent of the Bir-Aronov-Pikus process where exchange occurs with valence band hole states. Through low-temperature experiments with silicon spin transport devices and complementary theory, we reveal the consequences of this previously unknown spin depolarization mechanism both below and above the impact ionization threshold.
%U http://arxiv.org/abs/1308.5621v3