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arXiv · 0911.0911

Aharonov-Bohm conductance through a single-channel quantum ring: Persistent-current blockade and zero-mode dephasing

A. P. Dmitriev·I. V. Gornyi·V. Yu. Kachorovskii·D. G. Polyakov
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Abstract

We study the effect of electron-electron interaction on transport through a tunnel-coupled single-channel ring. We find that the conductance as a function of magnetic flux shows a series of interaction-induced resonances that survive thermal averaging. The period of the series is given by the interaction strength $α$. The physics behind this behavior is the blocking of the tunneling current by the circular current. The main mechanism of dephasing is due to circular-current fluctuations. The dephasing rate is proportional to the tunneling rate and does not depend on $α$.

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A. P. Dmitriev, I. V. Gornyi, V. Yu. Kachorovskii, D. G. Polyakov. 2010-04-29. Aharonov-Bohm conductance through a single-channel quantum ring: Persistent-current blockade and zero-mode dephasing. https://doi.org/10.1103/physrevlett.105.036402

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