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arXiv · 0907.1490

Robust coupling of superconducting order parameter in a mesoscale NbN-Fe-NbN epitaxial structure

S. K. Bose·R. C. Budhani
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Abstract

We report an unconventional and promising route to self-assemble distributed superconductor-ferromagnet-superconductor (S-F-S) Josephson Junctions on single crystal [100] MgO. These structures consist of [110] epitaxial nano-plaquettes of Fe covered with superconducting NbN films of varying thickness. The S-F-S structures are characterized by strong magnetoresistance (MR) anisotropy for the in-plane and out-of-plane magnetic fields. The stronger in-plane MR suggests decoherence of S-F-S junctions whose critical current follows a (1-T/Tc) and (1-T/Tc)1/2 dependence for T Tc and T<<Tc respectively, in accordance with the theory of supercurrent transport in such junctions.

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S. K. Bose, R. C. Budhani. 2009-07-09. Robust coupling of superconducting order parameter in a mesoscale NbN-Fe-NbN epitaxial structure. https://doi.org/10.1063/1.3189284

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