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arXiv · 1504.07412

Steady-state thermodynamics of non-interacting transport beyond weak coupling

Gabriel E. Topp·Tobias Brandes·Gernot Schaller
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Abstract

We investigate the thermodynamics of simple (non-interacting) transport models beyond the scope of weak coupling. For a single fermionic or bosonic level -- tunnel-coupled to two reservoirs -- exact expressions for the stationary matter and energy current are derived from the solutions of the Heisenberg equations of motion. The positivity of the steady-state entropy production rate is demonstrated explicitly. Finally, for a configuration in which particles are pumped upwards in chemical potential by a downward temperature gradient, we demonstrate that the thermodynamic efficiency of this process decreases when the coupling strength between system and reservoirs is increased, as a direct consequence of the loss of a tight coupling between energy and matter currents.

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Gabriel E. Topp, Tobias Brandes, Gernot Schaller. 2015-04-28. Steady-state thermodynamics of non-interacting transport beyond weak coupling. https://doi.org/10.1209/0295-5075/110/67003

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