Abstract
We investigate transport and thermoelectric properties of hybrid systems based on a single-level quantum dot and one superconducting lead. The other lead is generally normal-metallic ferromagnet. In the latter case, single-particle transport is spin polarized. Our main interest is in the interplay of Andreev tunneling of Cooper pairs and single-particle tunneling. The latter is responsible for relatively large thermopower and figure of merit due to a diverging density of single-particle states at the superconducting gap edges. A system with ferromagnetic and superconducting leads can also reveal spin thermoelectric phenomena. A finite superconducting gap is considered within the BCS theory, and the thermoelectric coefficients are calculated by means of nonequilibrium Green's function technique within Hartree-Fock–type approximation with respect to the intradot Coulomb interaction.
1 More- Received 13 November 2016
- Revised 25 March 2017
DOI:https://doi.org/10.1103/PhysRevB.95.165439
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