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arXiv · 1609.03707

Efficiency bounds on thermoelectric transport in magnetic fields: The role of inelastic processes

Kaoru Yamamoto·Ora Entin-Wohlman·Amnon Aharony·Naomichi Hatano
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Abstract

We examine the efficiency of an effective two-terminal thermoelectric device under broken time-reversal symmetry. The setup is derived from a three-terminal thermoelectric device comprising a thermal terminal and two electronic contacts, under a magnetic field. We find that breaking time-reversal symmetry in the presence of the inelastic electron-phonon processes can significantly enhance the figure of merit for delivering electric power by supplying heat from a phonon bath, beyond the one for producing the electric power by investing thermal power from the electronic heat current. The efficiency of such a device is bounded by the non-negativity of the entropy production of the original three-terminal junction. The efficiency at maximal power can be quite close to the Carnot efficiency, but then the electric power vanishes.

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Kaoru Yamamoto, Ora Entin-Wohlman, Amnon Aharony, Naomichi Hatano. 2016-09-13. Efficiency bounds on thermoelectric transport in magnetic fields: The role of inelastic processes. https://doi.org/10.1103/physrevb.94.121402

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