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arXiv · 1101.5121

Persistent current noise and electron-electron interactions

Andrew G. Semenov·Andrei D. Zaikin
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Abstract

We analyze fluctuations of persistent current (PC) produced by a charged quantum particle moving in a ring and interacting with a dissipative environment formed by diffusive electron gas. We demonstrate that in the presence of interactions such PC fluctuations persist down to zero temperature. In the case of weak interactions and/or sufficiently small values of the ring radius $R$ PC noise remains coherent and can be tuned by external magnetic flux $Φ_x$ piercing the ring. In the opposite limit of strong interactions and/or large values of $R$ fluctuations in the electronic bath strongly suppress quantum coherence of the particle down to $T=0$ and induce incoherent $Φ_x$-independent current noise in the ring which persists even at $Φ_x=0$ when the average PC is absent.

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Andrew G. Semenov, Andrei D. Zaikin. 2011-01-26. Persistent current noise and electron-electron interactions. https://doi.org/10.1103/physrevb.84.045416

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