Aharonov-Bohm oscillations in coupled quantum dots: Effect of electron-electron interactions

TL;DR

This paper theoretically investigates how electron-electron interactions diminish Aharonov-Bohm oscillation amplitudes in quantum dot rings, highlighting electron dephasing as the primary cause and providing testable predictions.

Contribution

It presents a quantitative analysis of interaction-induced suppression of AB oscillations in metallic quantum dots, emphasizing electron dephasing over Coulomb blockade effects.

Findings

Electron-electron interactions suppress AB oscillation amplitude at all temperatures.

Dephasing, not Coulomb blockade, is the main physical mechanism.

Quantitative predictions for future experimental verification.

Abstract

We theoretically analyze the effect of electron-electron interactions on Aharonov-Bohm (AB) current oscillations in ring-shaped systems with metallic quantum dots pierced by external magnetic field. We demonstrate that electron-electron interactions suppress the amplitude of AB oscillations $I_{AB}$ at all temperatures down to T=0 and formulate quantitative predictions which can be verified in future experiments. We argue that the main physical reason for such interaction-induced suppression of $I_{AB}$ is electron dephasing while Coulomb blockade effects remain insignificant in the case of metallic quantum dots considered here. We also emphasize a direct relation between our results and the so-called $P(E)$-theory describing tunneling of interacting electrons.