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arXiv · 1906.05401

The role of metallic leads and electronic degeneracies in thermoelectric power generation in quantum dots

Achim Harzheim·Jakub K. sowa·Jacob L. Swett·G. Andrew D. Briggs·Jan A. Mol·Pascal Gehring
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Abstract

The power factor of a thermoelectric device is a measure of the heat-to-energy conversion efficiency in nanoscopic devices. Yet, even as interest in low-dimensional thermoelectric materials has increased, experimental research on what influences the power factor in these systems is scarce. Here, we present a detailed thermoelectric study of graphene quantum dot devices. We show that spin-degeneracy of the quantum dot states has a significant impact on the zero-bias conductance of the device and leads to an increase of the power factor. Conversely, we demonstrate that non-ideal heat exchange within the leads can suppress the power factor near the charge degeneracy point and non-trivially influences its temperature dependence.

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Achim Harzheim, Jakub K. sowa, Jacob L. Swett, G. Andrew D. Briggs, Jan A. Mol, Pascal Gehring. 2019-06-12. The role of metallic leads and electronic degeneracies in thermoelectric power generation in quantum dots. https://doi.org/10.1103/physrevresearch.2.013140

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