Evidence for Triplet Superconductivity in a Superconductor-Ferromagnet Spin Valve

P. V. Leksin; N. N. Garif'yanov; I. A. Garifullin; Ya. V. Fominov; J. Schumann; Y. Krupskaya; V. Kataev; O. G. Schmidt; B. Büchner

doi:10.1103/physrevlett.109.057005

arXiv · 1207.0727

Evidence for Triplet Superconductivity in a Superconductor-Ferromagnet Spin Valve

P. V. Leksin·N. N. Garif'yanov·I. A. Garifullin·Ya. V. Fominov·J. Schumann·Y. Krupskaya·V. Kataev·O. G. Schmidt·B. Büchner

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Abstract

We have studied the dependence of the superconducting (SC) transition temperature on the mutual orientation of magnetizations of Fe1 and Fe2 layers in the spin valve system CoO_x/Fe1/Cu/Fe2/Pb. We find that this dependence is nonmonotonic when passing from the parallel to the antiparallel case and reveals a distinct minimum near the orthogonal configuration. The analysis of the data in the framework of the SC triplet spin valve theory gives direct evidence for the long-range triplet superconductivity arising due to noncollinearity of the two magnetizations.

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P. V. Leksin, N. N. Garif'yanov, I. A. Garifullin, Ya. V. Fominov, J. Schumann, Y. Krupskaya, V. Kataev, O. G. Schmidt, B. Büchner. 2012-07-03. Evidence for Triplet Superconductivity in a Superconductor-Ferromagnet Spin Valve. https://doi.org/10.1103/physrevlett.109.057005

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