Electron-acoustic-phonon scattering and electron relaxation in two-coupled quantum rings

TL;DR

This paper investigates how acoustic phonons induce electron relaxation in coupled quantum rings, revealing oscillatory behavior in scattering rates influenced by external fields and system geometry.

Contribution

It provides a detailed analysis of electron-phonon interactions in coupled quantum rings, considering both deformation potential and piezoelectric coupling mechanisms, under various external conditions.

Findings

Oscillations in scattering rates depend on system geometry and external fields.

Different electron-phonon couplings have varying significance based on external conditions.

External fields and geometry significantly influence electron relaxation processes.

Abstract

Electron relaxation, induced by acoustic phonons, is studied for coupled quantum rings in the presence of external fields, both electric and magnetic. We address the problem of a single electron in vertically coupled GaAs quantum rings. Electron-phonon interaction is accounted for both deformation potential and piezoelectric field coupling mechanisms. Depending on the external fields, the ring radii and the separation between the rings, we show that the two different couplings have different weights and importance. Significant oscillations are found in the scattering rates from electron excited states to the ground state, as a function of either the geometry of the system or the external fields.