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تسجيل مستخدم جديدControllable supercurrent in mesoscopic superconductor-normal metal-ferromagnet crosslike Josephson structures
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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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