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arXiv · 1403.1807

Quantum transport, master equations, and exchange fluctuations

Robert Hussein·Sigmund Kohler
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Abstract

We investigate to which extent a many-body Bloch-Redfield master equation description of quantum transport is consistent with the exact generalized equilibrium conditions known as exchange fluctuation theorems. Thereby we identify a class of master equations for which this is the case. Beyond this class, we find deviations which exhibit characteristic scaling laws as functions of the dot-lead tunneling, the inter-dot tunneling, and the temperature. These deviations are accompanied by an increase of lead energy fluctuations inherent in the Bloch-Redfield equation beyond rotating-wave approximation. We illustrate our results with numerical data for a double quantum dot attached to four leads.

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Robert Hussein, Sigmund Kohler. 2014-03-07. Quantum transport, master equations, and exchange fluctuations. https://doi.org/10.1103/physrevb.89.205424

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