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All-MgB2 Josephson tunnel junctions

K. Ueda·S. Saito·K. Semba·T. Makimoto·M. Naito
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Abstract

Sandwich-type all-MgB2 Josephson tunnel junctions (MgB2/AlOx/MgB2) have been fabricated for the first time with as-grown MgB2 films formed by molecular beam epitaxy. The junctions exhibit substantial superconducting current (IcRN product ~ 0.8 mV at 4.2K), a well-defined superconducting gap (delta = ~2.3 mV), and clear Fraunhofer patterns. The superconducting gap voltage of delta agrees well with the smaller gap in the multi-gap scenario. The results demonstrate that MgB2 has great promise for superconducting electronics that can be operated at T ~ 20 K.

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K. Ueda, S. Saito, K. Semba, T. Makimoto, M. Naito. 2004-12-14. All-MgB2 Josephson tunnel junctions. https://doi.org/10.1063/1.1920411

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