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arXiv · 1712.05966

Fabrication of grain boundary junctions using NdFeAs(O,F) superconducting thin films

Taito Omura·Takuya Matsumoto·Takafumi Hatano·Kazumasa Iida·Hiroshi Ikuta
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Abstract

We report on the growth of NdFeAs(O,F) thin films on [001]-tilt MgO bicrystal substrates with misorientation angle theta_GB=6{\deg}, 12{\deg}, 24{\deg} and 45{\deg}, and their inter- and intra-grain transport properties. X-ray diffraction study confirmed that all our NdFeAs(O,F) films are epitaxially grown on the MgO bicrystals. The theta_GB dependence of the inter-grain critical current density Jc shows that, unlike Co-doped BaFe2As2 and Fe(Se,Te), its decay with theta_GB is rather significant. As a possible reason of this result, fluorine may have diffused preferentially to the grain boundary region and eroded the crystal structure.

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Taito Omura, Takuya Matsumoto, Takafumi Hatano, Kazumasa Iida, Hiroshi Ikuta. 2017-12-16. Fabrication of grain boundary junctions using NdFeAs(O,F) superconducting thin films. https://doi.org/10.1088/1742-6596%2F1054%2F1%2F012024

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