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Non-equilibrium supercurrent through mesoscopic ferromagnetic weak links

Tero T. Heikkila·Frank K. Wilhelm·Gerd Schoen
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Abstract

We consider a mesoscopic normal metal, where the spin degeneracy is lifted by a ferromagnetic exchange field or Zeeman splitting, coupled to two superconducting reservoirs. As a function of the exchange field or the distance between the reservoirs, the supercurrent through this device oscillates with an exponentially decreasing envelope. This phenomenon is similar to the tuning of a supercurrent by a non-equilibrium quasiparticle distribution between two voltage-biased reservoirs. We propose a device combining the exchange field and non-equilibrium effects, which allows us to observe a range of novel phenomena. For instance, part of the field-suppressed supercurrent can be recovered by a voltage between the additional probes.

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Tero T. Heikkila, Frank K. Wilhelm, Gerd Schoen. 2000-06-15. Non-equilibrium supercurrent through mesoscopic ferromagnetic weak links. https://doi.org/10.1209/epl%2Fi2000-00513-x

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