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arXiv · 0904.2983

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

Andrew G. Semenov·Dmitri S. Golubev·Andrei D. Zaikin
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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.

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Andrew G. Semenov, Dmitri S. Golubev, Andrei D. Zaikin. 2009-04-20. Aharonov-Bohm oscillations in coupled quantum dots: Effect of electron-electron interactions. https://doi.org/10.1103/physrevb.79.115302

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