Spin relaxation via exchange with donor impurity-bound electrons
Abstract
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.
Cite
@article{arxiv.1308.5621,
title = {Spin relaxation via exchange with donor impurity-bound electrons},
author = {Lan Qing and Jing Li and Ian Appelbaum and Hanan Dery},
journal= {arXiv preprint arXiv:1308.5621},
year = {2015}
}