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arXiv · 1503.02297

Cross thermoelectric coupling in normal-superconductor quantum dots

Sun-Yong Hwang·Rosa Lopez·David Sanchez
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Abstract

We discuss the nonlinear current of an interacting quantum dot coupled to normal and superconducting reservoirs with applied voltage and temperature differences. Due to the particle-hole symmetry introduced by the superconducting lead, the pure (subgap) thermoelectric response vanishes. However, we show that the Andreev bound states shift as the thermal gradient increases. As a consequence, the $I$--$V$ characteristic can be tuned with a temperature bias if the system is simultaneously voltage biased. This is a cross effect that occurs beyond linear response only. Furthermore, we emphasize the role of quasiparticle tunneling processes in the generation of high thermopower sensitivities.

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Sun-Yong Hwang, Rosa Lopez, David Sanchez. 2015-03-08. Cross thermoelectric coupling in normal-superconductor quantum dots. https://doi.org/10.1103/physrevb.91.104518

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