Crossover from diffusive to non-diffusive dynamics in the two-dimensional electron gas with Rashba spin-orbit coupling

TL;DR

This paper derives a comprehensive response function for a 2D electron gas with Rashba spin-orbit coupling, capturing the transition from diffusive to non-diffusive regimes and analyzing charge and spin modes relevant for experiments.

Contribution

It provides a unified microscopic framework for understanding the crossover between diffusive and non-diffusive electron dynamics in Rashba systems.

Findings

Derived response functions applicable across regimes

Identified propagating charge and spin modes in the clean limit

Provided insights relevant for modern experimental setups

Abstract

We present the calculation of the density matrix response function of the two-dimensional electron gas with Rashba spin-orbit interaction, which is applicable in a wide range of parameters covering the diffusive and non-diffusive, the dirty and the clean limits. A description of the crossover between the different regimes is thus provided as well. On the basis of the derived microscopic expressions we study the propagating charge and spin-polarization modes in the clean, non-diffusive regime, which is accessible in the modern experiments.