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arXiv · 1608.02414

Mixed electrical-heat noise spectrum in a quantum dot

Paul Eyméoud·Adeline Crépieux
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Abstract

Using the Keldysh Green function technique, we calculate the finite-frequency correlator between the electrical current and the heat current flowing through a quantum dot connected to reservoirs. At equilibrium, we find that this quantity, called mixed noise, is linked to the thermoelectric ac-conductance by the fluctuation-dissipation theorem. Out-of-equilibrium, we discuss its spectrum and find evidence of the close relationship between the mixed noise and the thermopower. We study the spectral coherence and identify the conditions to have a strong correlation between the electrical and heat currents. The change in the spectral coherence due to the presence of a temperature gradient between the reservoirs is also highlighted.

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Paul Eyméoud, Adeline Crépieux. 2016-08-08. Mixed electrical-heat noise spectrum in a quantum dot. https://doi.org/10.1103/physrevb.94.205416

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