Theory of Rashba spin-orbit coupling in magnetic metals is worked out from microscopic Hamiltonian describing d-orbitals. When structural inversion symmetry is broken, electron hopping between d-orbitals generates chiral ordering of orbital angular momentum, which combines with atomic spin-orbit coupling to result in the Rashba interaction. Rashba parameter characterizing the interaction is band-specific, even reversing its sign from band to band. Large enhancement of the Rashba parameter found in recent experiments is attributed to the orbital mixing of 3d magnetic atoms with non-magnetic heavy elements as we demonstrate by first-principles and tight-binding calculations.
@article{arxiv.1207.0089,
title = {Microscopic Theory of Rashba Interaction in Magnetic Metal},
author = {Jin-Hong Park and Choong H. Kim and Hyun-Woo Lee and Jung Hoon Han},
journal= {arXiv preprint arXiv:1207.0089},
year = {2013}
}