Microscopic Linear Response Theory of Spin Relaxation and Relativistic Transport Phenomena in Graphene
AbstractWe 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-Text
Share & Cite This Article
Offidani, M.; Raimondi, R.; Ferreira, A. Microscopic Linear Response Theory of Spin Relaxation and Relativistic Transport Phenomena in Graphene. Condens. Matter 2018, 3, 18.
Offidani M, Raimondi R, Ferreira A. Microscopic Linear Response Theory of Spin Relaxation and Relativistic Transport Phenomena in Graphene. Condensed Matter. 2018; 3(2):18.Chicago/Turabian Style
Offidani, Manuel; Raimondi, Roberto; Ferreira, Aires. 2018. "Microscopic Linear Response Theory of Spin Relaxation and Relativistic Transport Phenomena in Graphene." Condens. Matter 3, no. 2: 18.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.