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

TL;DR

This paper investigates how Rashba and Dresselhaus spin-orbit coupling influence thermoelectric transport in quantum dots, revealing enhanced thermoelectric efficiency and the system's behavior in the Kondo regime.

Contribution

It provides a detailed analysis of spin-orbit effects on thermoelectric properties in quantum dots using numerical renormalization group methods, highlighting the universality and increased figure of merit.

Findings

Spin-orbit coupling drives the system into the Kondo regime.

Thermoelectric properties obey the universality of the Kondo fixed point.

Spin-orbit coupling increases the thermoelectric figure of merit.

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.