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Double-reversal thickness dependence of critical current in superconductor-ferromagnet-superconductor Josephson junctions

V. A. Oboznov·V. V. Bol'ginov·A. K. Feofanov·V. V. Ryazanov·A. I. Buzdin
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Abstract

We report the first experimental observation of the two-node thickness dependence of the critical current in Josephson junctions with a ferromagnetic interlayer. Vanishings of the critical current correspond to transitions into pi-state and back into conventional 0-state. The experimental data allow to extract the superconducting order parameter oscillation period and the pair decay length in the ferromagnet. We develope a theoretical approach based on Usadel equations, which takes into account the spin-flip scattering. Results of numerical calculations are in good agreement with the experimental data.

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V. A. Oboznov, V. V. Bol'ginov, A. K. Feofanov, V. V. Ryazanov, A. I. Buzdin. 2005-08-24. Double-reversal thickness dependence of critical current in superconductor-ferromagnet-superconductor Josephson junctions. https://arxiv.org/abs/cond-mat/0508573

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