title: A unified theory of spin-relaxation due to spin-orbit coupling in metals and semiconductors.
abstract: Spintronics is an emerging paradigm with the aim to replace conventional electronics by using electron spins as information carriers. Its utility relies on the magnitude of the spin-relaxation, which is dominated by spin-orbit coupling (SOC). Yet, SOC induced spin-relaxation in metals and semiconductors is discussed for the seemingly orthogonal cases when inversion symmetry is retained or broken by the so-called Elliott-Yafet and D'yakonov-Perel' spin-relaxation mechanisms, respectively. We unify the two theories on general grounds for a generic two-band system containing intra- and inter-band SOC. While the previously known limiting cases are recovered, we also identify parameter domains when a crossover occurs between them, i.e. when an inversion symmetry broken state evolves from a D'yakonov-Perel' to an Elliott-Yafet type of spin-relaxation and conversely for a state with inversional symmetry. This provides an ultimate link between the two mechanisms of spin-relaxation.
authors.affiliation: 1] Department of Physics, Budapest University of Technology and Economics, Budapest, Hungary [2] Department of Materials Physics, Eötvös University, Budapest, Hungary.
authors.forename: Péter
authors.initials: P
authors.lastname: Boross
authors.forename: Balázs
authors.initials: B
authors.lastname: Dóra
authors.forename: Annamária
authors.initials: A
authors.lastname: Kiss
authors.forename: Ferenc
authors.initials: F
authors.lastname: Simon