Electron correlations due to pair spin-orbit interaction in 2D electron systems

TL;DR

This paper demonstrates that pair spin-orbit interaction in 2D electron systems can induce a striped electronic phase, characterized by a peak in the structure factor, leading to charge density instabilities at strong PSOI.

Contribution

It introduces the concept that Coulomb-induced pair spin-orbit interaction can cause unconventional correlated states and charge density wave tendencies in 2D materials with large Rashba effect.

Findings

Sharp peak in structure factor indicating stripe formation

Charge density fluctuations become unstable at critical PSOI

System exhibits a phase transition driven by PSOI strength

Abstract

We show that the pair spin-orbit interaction (PSOI) created by the Coulomb fields of interacting electrons leads to the appearance of an unconventional correlated electronic state in two-dimensional materials with the large Rashba effect. The effect manifests itself at sufficiently strong PSOI as a sharp peak in the structure factor, indicating a tendency to form a striped structure with a spatial scale determined by the competition between the Coulomb repulsion and the PSOI-induced attraction of electrons. Above the critical value of PSOI, the system becomes unstable with respect to the charge density fluctuations on this scale.