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arXiv · 1411.1717

Enhancement of thermoelectric effect in diffusive superconducting bilayers with magnetic interfaces

Mikhail S. Kalenkov·Andrei D. Zaikin
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Abstract

We demonstrate that thermoelectric currents in superconducting bilayers with a spin-active interface are controlled by the two competing processes. On one hand, spin-sensitive quasiparticle scattering at such interface generates electron-hole imbalance and yields orders-of-magnitude enhancement of the thermoelectric effect in the system. On the other hand, this electron-hole imbalance gets suppressed in the superconductor bulk due to electron scattering on non-magnetic impurities. As a result, large thermoelectric currents can only flow in the vicinity of the spin-active interface and decay away from this interface at a distance exceeding the electron elastic mean free path $\ell$. The magnitude of the thermoelectric effect reaches its maximum provided $\ell$ becomes of order of the total bilayer thickness.

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Mikhail S. Kalenkov, Andrei D. Zaikin. 2014-11-06. Enhancement of thermoelectric effect in diffusive superconducting bilayers with magnetic interfaces. https://doi.org/10.1103/physrevb.91.064504

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