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Giant fluctuations of superconducting order parameter in Ferromagnet/superconductor single electron transistors

J. Johansson·V. Korenivski·D. B. Haviland·A. Brataas
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Abstract

Spin dependent transport in a ferromagnet/superconductor/ferromagnet single electron transistor is studied theoretically with spin accumulation, spin relaxation, gap suppression, and charging effects taken into account. A strong dependence of the gap on the magnetic state of the outer electrodes is found, which gives rise to a negative magneto-resistance of up to 100 %. We predict that fluctuations of the spin accumulation due to tunneling of quasi-particles can play such an important role as to cause the island to fluctuate between the superconducting

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J. Johansson, V. Korenivski, D. B. Haviland, A. Brataas. 2004-03-11. Giant fluctuations of superconducting order parameter in Ferromagnet/superconductor single electron transistors. https://doi.org/10.1103/physrevlett.93.216805

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