FisMat2017 - Submission - View

Abstract's title: Weak localization corrections to the spin transport coefficients in two-dimensional electron gases in the presence of Rashba spin-orbit coupling
Submitting author: Daniele Guerci
Affiliation: SISSA
Affiliation Address: Via Bonomea, 265
Country: Italy
Oral presentation/Poster (Author's request): Oral presentation
Other authors and affiliations: Roberto Raimondi, Università degli studi di Roma Tre, Roma Juan Borge, Nano-bio Spectroscopy Group, San Sebastian
Abstract

Weak localization (WL) is the result of quantum interference corrections to the semi-

classical theory of transport. It manifests itself in good conductors as a negative

or positive correction to the electrical conductivity depending on the symmetry properties

of the system. In the presence of spin-orbit coupling (SOC), the correction is positive and

hence manifests as an antilocalizing behavior. SOC affects WL because it yields a finite

spin relaxation time, which introduces a cutoff in the logarithmic singularity associated

with the so-called triplet channel of the particle-particle ladder, known as the Cooperon.

Since the singlet and the triplet channels contribute to WL with opposite signs, the eli-

mination of the triplet leaves the singlet alone, which then produces the antilocalizing

behavior. WL effects in the presence of the Rashba SOC  have been

analyzed by several authors, most of the attention having been focused on the electrical

conductivity only. It is the aim of the present work to extend this ana-

lysis to the other transport parameters mentioned above, whose experimental study has

developed considerably in the last few years. We find that σEC and the spin Hall

angle γSH = SHC/σ0 acquire logarithmic corrections which can be absorbed in terms drift

of the renormalization of the scattering time appearing in the electrical conductivity σ0.

We emphasize that σSHC is not the full spin conductivity σSHC which would be measured

in an experiment. It can be proved that σSHC can be expressed in terms of σEC and

σSHC. The renormalizations of both σEC and γSH compensate in such a way that σSHC drift

has no correction as expected on general arguments.