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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Modeling the effects of dephasing on mesoscopic noise

Marco G. Pala, Giuseppe Iannaccone, Massimo Macucci, Giovanni Marola

Published May 25, 2004• 0 citations
Publisher

Abstract

We present simulations of the effects of dephasing on the shot noise properties of mesoscopic coherent devices, such as chaotic cavities and Aharonov-Bohm rings. We adopt a phenomenological model that exploits the statistical nature of the dephasing mechanism and is able to cover the intermediate regime between a fully coherent and completely incoherent (i.e., semiclassical) transport. By investigating conductance and noise properties as a function of the dephasing length, we conclude that decoherence has no specific effect on shot noise which can be distinguished from the one it has on conductance. In addition, when a large number of conducting channels is considered, semiclassical and quantum behavior must converge, yielding as a consequence the independence of DC and noise properties from dephasing.

DOI
10.1117/12.548604

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