Spin Hall conductivity of interacting two-dimensional electron systems

TL;DR

This paper investigates how electron interactions, disorder, and spin-orbit coupling influence the spin Hall conductivity in two-dimensional electron systems, providing a detailed theoretical analysis of their combined effects.

Contribution

It introduces a kinetic equation approach within the Keldysh formalism to analyze interaction effects on spin Hall conductivity in 2D systems with Rashba coupling.

Findings

Interaction corrections are linked to quantum interference effects.

Frequency dependence of spin Hall conductivity is characterized.

Finite temperature effects on transport regimes are discussed.

Abstract

We consider a two-dimensional electron system subjected to a short-ranged nonmagnetic disorder potential, Coulomb interactions, and Rashba spin-orbit coupling. The path-integral approach incorporated within the Keldysh formalism is used to derive the kinetic equation for the semiclassical Green's function and applied to compute the spin current within the linear response theory. We discuss the frequency dependence of the spin Hall conductivity and further elucidate the role of electron interactions at finite temperatures for both the ballistic and diffusive regimes of transport. We argue that interaction corrections to the spin Hall effect stem from the quantum interference processes whose magnitude is estimated in terms of parameters of the considered model.