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arXiv · 1611.02032

Large thermoelectric effect in ballistic Andreev interferometers

Mikhail S. Kalenkov·Andrei D. Zaikin
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Abstract

Employing quasiclassical theory of superconductivity combined with Keldysh technique we investigate large thermoelectric effect in multiterminal ballistic normal-superconducting (NS) hybrid structures. We argue that this effect is caused by electron-hole asymmetry generated by coherent Andreev reflection of quasiparticles at interfaces of two different superconductors with non-zero phase difference. Within our model we derive a general expression for thermoelectric voltages $V_{T1,2}$ induced in two different normal terminals exposed to a thermal gradient. Our results apply at any temperature difference in the subgap regime and allow to explicitly analyze both temperature and phase dependencies of $V_{T1,2}$ demonstrating that in general there exists no fundamental relation between these voltages and the equilibrium Josephson current in SNS junctions.

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Mikhail S. Kalenkov, Andrei D. Zaikin. 2016-11-07. Large thermoelectric effect in ballistic Andreev interferometers. https://doi.org/10.1103/physrevb.95.024518

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