Electron-hole imbalance and large thermoelectric effect in superconducting hybrids with spin-active interfaces

Mikhail S. Kalenkov; Andrei D. Zaikin

doi:10.1103/physrevb.90.134502

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arXiv · 1405.3858

Electron-hole imbalance and large thermoelectric effect in superconducting hybrids with spin-active interfaces

Mikhail S. Kalenkov·Andrei D. Zaikin

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Abstract

We argue that spin-sensitive quasiparticle scattering may generate electron-hole imbalance in superconducting structures, such as, e.g., superconducting-normal hybrids with spin-active interfaces. We elucidate a transparent physical mechanism for this effect demonstrating that scattering rates for electrons and holes at such interfaces differ from each other. Explicitly evaluating the wave functions of electron-like and hole-like excitations in superconducting-normal bilayers we derive a general expression for the thermoelectric current and show that -- in the presence of electron-hole imbalance -- this current can reach maximum values as high as the critical current of a superconductor.

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Mikhail S. Kalenkov, Andrei D. Zaikin. 2014-05-15. Electron-hole imbalance and large thermoelectric effect in superconducting hybrids with spin-active interfaces. https://doi.org/10.1103/physrevb.90.134502

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