Tuning of few-electron states and optical absorption anisotropy in GaAs quantum rings

TL;DR

This paper theoretically investigates how Rashba and Dresselhaus spin-orbit interactions affect the electronic and optical properties of GaAs quantum rings with few electrons, revealing tunable anisotropy and control mechanisms.

Contribution

It introduces a comprehensive theoretical analysis of multi-electron states and optical anisotropy in GaAs quantum rings considering spin-orbit interactions and Coulomb effects, offering new control strategies.

Findings

Spin-orbit interactions induce anisotropic multi-electron state distributions.

Coulomb interactions modulate electron distribution and optical absorption.

External fields and electron number tuning significantly alter optical properties.

Abstract

The electronic and optical properties of a GaAs quantum ring (QR) with few electrons in the presence of the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI) have been investigated theoretically. Configuration interaction (CI) method is employed to calculate the eigenvalues and eigenstates of the multiple-electron QR accurately. Our numerical results demonstrate that the symmetry breaking induced by the RSOI and DSOI leads to an anisotropic distribution of multi-electron states. The Coulomb interaction offers additional modulation of the electron distribution and thus the optical absorption indices in the quantum rings. By tuning the magnetic/electric fields and/or electron numbers in a quantum ring, one can change its optical property significantly. Our theory provides a new way to control multi-electron states and optical properties of QR by hybrid modulations or by electrical means only.