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arXiv · 1101.4124

Mechanism for large thermoelectric power in negative-U molecular quantum dots

S. Andergassen·T. A. Costi·V. Zlatic
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Abstract

We investigate with the aid of numerical renormalization group techniques the thermoelectric properties of a molecular quantum dot described by the negative-U Anderson model. We show that the charge Kondo effect provides a mechanism for enhanced thermoelectric power via a correlation induced asymmetry in the spectral function close to the Fermi level. We show that this effect results in a dramatic enhancement of the Kondo induced peak in the thermopower of negative-U systems with Seebeck coefficients exceeding 50$μV/K$ over a wide range of gate voltages.

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S. Andergassen, T. A. Costi, V. Zlatic. 2011-12-14. Mechanism for large thermoelectric power in negative-U molecular quantum dots. https://doi.org/10.1103/physrevb.84.241107

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