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arXiv · 1208.5629

Triplet supercurrent in ferromagnetic Josephson junctions by spin injection

A. G. Mal'shukov·Arne Brataas
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Abstract

We show that injecting nonequilibrium spins into the superconducting leads strongly enhances the stationary Josephson current through a superconductor-ferromagnet-superconductor junction. The resulting long-range super-current through a ferromagnet is carried by triplet Cooper pairs that are formed in s-wave superconductors by the combined effects of spin injection and exchange interaction. We quantify the exchange interaction in terms of Landau Fermi-liquid factors. The magnitude and direction of the long-range Josephson current can be manipulated by varying the angles of the injected polarizations with respect to the magnetization in the ferromagnet.

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A. G. Mal'shukov, Arne Brataas. 2012-08-28. Triplet supercurrent in ferromagnetic Josephson junctions by spin injection. https://doi.org/10.1103/physrevb.86.094517

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