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arXiv · 1012.4846

Persistent current noise

Andrew G. Semenov·Andrei D. Zaikin
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Abstract

We demonstrate that persistent current in meso- and nanorings may fluctuate down to zero temperature provided the current operator does not commute with the total Hamiltonian of the system. For a model of a quantum particle on a ring we explicitly evaluate PC noise power which has a form of sharp peaks which become broadened for multi-channel rings or in the presence of dissipation. PC noise can be tuned by an external magnetic flux which is a fundamental manifestation of quantum coherence in the system.

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Andrew G. Semenov, Andrei D. Zaikin. 2010-12-22. Persistent current noise. https://doi.org/10.1088/1742-6596%2F248%2F1%2F012034

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