%0 Journal Article
%T Microscopic Linear Response Theory of Spin Relaxation and Relativistic Transport Phenomena in Graphene
%A Aires Ferreira
%A Manuel Offidani
%A Roberto Raimondi
%J Condensed Matter | An Open Access Journal from MDPI
%D 2018
%R https://doi.org/10.3390/condmat3020018
%X Abstract We present a unified theoretical framework for the study of spin dynamics and relativistic transport phenomena in disordered two-dimensional Dirac systems with pseudospin-spin coupling. The formalism is applied to the paradigmatic case of graphene with uniform Bychkov-Rashba interaction and shown to capture spin relaxation processes and associated charge-to-spin interconversion phenomena in response to generic external perturbations, including spin density fluctuations and electric fields. A controlled diagrammatic evaluation of the generalized spin susceptibility in the diffusive regime of weak spin-orbit interaction allows us to show that the spin and momentum lifetimes satisfy the standard Dyakonov-Perel relation for both weak (Gaussian) and resonant (unitary) nonmagnetic disorder. Finally, we demonstrate that the spin relaxation rate can be derived in the zero-frequency limit by exploiting the SU(2) covariant conservation laws for the spin observables. Our results set the stage for a fully quantum-mechanical description of spin relaxation in both pristine graphene samples with weak spin-orbit fields and in graphene heterostructures with enhanced spin-orbital effects currently attracting much attention. View Full-Tex
%K graphene
%K spintronics
%K spin relaxation
%K 2DEGs
%K diagrammatic theory
%K spin-Galvanic effect
%K spin-orbit coupling
%U https://www.mdpi.com/2410-3896/3/2/18