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arXiv · 1003.5011

Tuning Excess Noise by Aharonov-Bohm Interferometry

Fabrizio Dolcini·Hermann Grabert
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Abstract

A voltage bias applied to a conductor induces a change of the current noise with respect to the equilibrium noise known as excess noise. We analyze the excess noise of the electronic current flowing through a mesoscopic Aharonov-Bohm ring threaded by a magnetic flux, coupled to a side gate, and contacted by two metallic electrodes. It is shown that the excess noise can be controlled both magnetically and electrostatically, demonstrating the full tunability of the system. At zero frequency, the ratio of the noise strength to the current (Fano factor) can thereby be minimized. Remarkably, at finite frequency, regions of negative excess noise emerge.

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Fabrizio Dolcini, Hermann Grabert. 2010-10-18. Tuning Excess Noise by Aharonov-Bohm Interferometry. https://doi.org/10.1016/j.chemphys.2010.03.028

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