Electronic charge and spin density distribution in a quantum ring with spin-orbit and Coulomb interactions

TL;DR

This study investigates how spin-orbit coupling and Coulomb interactions influence charge and spin densities in a quantum ring, revealing that Coulomb repulsion flattens charge density deformations but amplifies spin density variations.

Contribution

It provides an exact numerical analysis of charge and spin densities in a quantum ring with multiple electrons, incorporating both spin-orbit and Coulomb interactions for the first time.

Findings

Coulomb repulsion flattens charge-density deformations caused by SOI.

Coulomb interactions amplify spin-density variations.

Energy spectrum obtained via exact diagonalization for few-electron systems.

Abstract

Charge and spin density distributions are studied within a nano-ring structure endowed with Rashba and Dresselhaus spin orbit coupling (SOI). For a small number of interacting electrons, in the presence of an external magnetic field, the energy spectrum of the system is calculated through an exact numerical diagonalization procedure. The eigenstates thus determined are used to estimate the charge and spin densities around the ring. We find that when more than two electrons are considered, the charge-density deformations induced by SOI are dramatically flattened by the Coulomb repulsion, while the spin density ones are amplified.