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arXiv · 2106.02184

Spin-orbit coupling effects over thermoelectric transport properties in quantum dots

M. A. Manya·G. B. Martins·M. S. Figueira
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Abstract

We study the effects caused by Rashba and Dresselhaus spin-orbit coupling over the thermoelectric transport properties of a single-electron transistor, viz., a quantum dot connected to one-dimensional leads. Using linear response theory and employing the numerical renormalization group method, we calculate the thermopower, electrical and thermal conductances, dimensionless thermoelectric figure of merit, and study the Wiedemann-Franz law, showing their temperature maps. Our results for all those properties indicate that spin-orbit coupling drives the system into the Kondo regime. We show that the thermoelectric transport properties, in the presence of spin-orbit coupling, obey the expected universality of the Kondo strong coupling fixed point. In addition, our results show a notable increase in the thermoelectric figure of merit, caused by the spin-orbit coupling in the one-dimensional quantum dot leads.

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M. A. Manya, G. B. Martins, M. S. Figueira. 2021-06-04. Spin-orbit coupling effects over thermoelectric transport properties in quantum dots. https://doi.org/10.1103/physrevb.105.165421

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