Controllable supercurrent in mesoscopic superconductor-normal metal-ferromagnet crosslike Josephson structures

Tatiana E. Golikova; Michael J. Wolf; Detlef Beckmann; Grigory A. Penzyakov; Igor E. Batov; Irina V. Bobkova; Alexander M. Bobkov; Valery V. Ryazanov

doi:10.1088/1361-6668/abfd0d

arXiv · 2008.03217

Controllable supercurrent in mesoscopic superconductor-normal metal-ferromagnet crosslike Josephson structures

Tatiana E. Golikova·Michael J. Wolf·Detlef Beckmann·Grigory A. Penzyakov·Igor E. Batov·Irina V. Bobkova·Alexander M. Bobkov·Valery V. Ryazanov

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Abstract

A nonmonotonic dependence of the critical Josephson supercurrent on the injection current through a normal metal/ferromagnet weak link from a single domain ferromagnetic strip has been observed experimentally in nanofabricated planar crosslike S-N/F-S Josephson structures. This behavior is explained by 0-pi and pi-0 transitions, which can be caused by the suppression and Zeeman splitting of the induced superconductivity due to interaction between N and F layers, and the injection of spin-polarized current into the weak link. A model considering both effects has been developed. It shows the qualitative agreement between the experimental results and the theoretical model in terms of spectral supercurrent-carrying density of states of S-N/F-S structure and the spin-dependent double-step nonequilibrium quasiparticle distribution.

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Tatiana E. Golikova, Michael J. Wolf, Detlef Beckmann, Grigory A. Penzyakov, Igor E. Batov, Irina V. Bobkova, Alexander M. Bobkov, Valery V. Ryazanov. 2020-08-07. Controllable supercurrent in mesoscopic superconductor-normal metal-ferromagnet crosslike Josephson structures. https://doi.org/10.1088/1361-6668/abfd0d

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