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arXiv · 1706.08245

Colloquium: Nonequilibrium effects in superconductors with a spin-splitting field

F. Sebastian Bergeret·Mikhail Silaev·Pauli Virtanen·Tero T. Heikkila
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Abstract

We review the recent progress in understanding the properties of spin-split superconductors under non-equilibrium conditions. Recent experiments and theories demonstrate a rich variety of transport phenomena occurring in devices based on such materials that suggest direct applications in thermoelectricity, low-dissipative spintronics, radiation detection and sensing. We discuss different experimental situations and present a theoretical framework based on quantum kinetic equations. Within this framework we provide an accurate description of the non-equilibrium distribution of charge, spin and energy, which are the relevant non-equilibrium modes, in different hybrid structures. We also review experiments on spin-split superconductors and show how transport measurements reveal the properties of the non-equilibrium modes and their mutual coupling. We discuss in detail spin injection and diffusion and very large thermoelectric effects in spin-split superconductors.

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F. Sebastian Bergeret, Mikhail Silaev, Pauli Virtanen, Tero T. Heikkila. 2017-06-26. Colloquium: Nonequilibrium effects in superconductors with a spin-splitting field. https://doi.org/10.1103/revmodphys.90.041001

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