Mesoscopic fluctuations in the spin-electric susceptibility due to Rashba spin-orbit interaction

TL;DR

This paper studies how mesoscopic disorder causes large sample-to-sample fluctuations in spin polarization induced by electric fields in disordered 2D electron gases with Rashba spin-orbit interaction, revealing observable effects.

Contribution

It provides a diagrammatic analysis of mesoscopic fluctuations in spin-electric susceptibility, highlighting the significant sample-to-sample variations and their dependence on physical parameters.

Findings

Out-of-plane polarization exhibits large fluctuations in disordered samples.

Variance of susceptibility depends on magnetic field, spin-orbit strength, and dephasing.

Fluctuations are within experimental detection capabilities.

Abstract

We investigate mesoscopic fluctuations in the spin polarization generated by a static electric field and by Rashba spin-orbit interaction in a disordered 2D electron gas. In a diagrammatic approach we find that the out-of-plane polarization -- while being zero for self-averaging systems -- exhibits large sample-to-sample fluctuations which are shown to be well within experimental reach. We evaluate the disorder-averaged variance of the susceptibility and find its dependence on magnetic field, spin-orbit interaction, dephasing, and chemical potential difference.