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arXiv · 1512.07540

Density Functional Theory of the Seebeck coefficient in the Coulomb blockade regime

Kaike Yang·Enrico Perfetto·Stefan Kurth·Gianluca Stefanucci·Roberto D'Agosta
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Abstract

The Seebeck coefficient plays a fundamental role in identifying the efficiency of a thermoelectric device. Its theoretical evaluation for atomistic models is routinely based on Density Functional Theory calculations combined with the Landauer-Büttiker approach to quantum transport. This combination, however, suffers from serious drawbacks for devices in the Coulomb blockade regime. We show how to cure the theory through a simple correction in terms of the {\em temperature derivative} of the exchange correlation potential. Our results compare well with both rate equations and experimental findings on carbon nanotubes.

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Kaike Yang, Enrico Perfetto, Stefan Kurth, Gianluca Stefanucci, Roberto D'Agosta. 2015-12-23. Density Functional Theory of the Seebeck coefficient in the Coulomb blockade regime. https://doi.org/10.1103/physrevb.94.081410

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