Highly textured oxypnictide superconducting thin films on metal substrates

Kazumasa Iida; Fritz Kurth; Masashi Chihara; Naoki Sumiya; Vadim Grinenko; Ataru Ichinose; Ichiro Tsukada; Jens Hänisch; Vladimir Matias; Takafumi Hatano; Bernhard Holzapfel; Hiroshi Ikuta

doi:10.1063/1.4900931

arXiv · 1410.8743

Highly textured oxypnictide superconducting thin films on metal substrates

Kazumasa Iida·Fritz Kurth·Masashi Chihara·Naoki Sumiya·Vadim Grinenko·Ataru Ichinose·Ichiro Tsukada·Jens Hänisch·Vladimir Matias·Takafumi Hatano·Bernhard Holzapfel·Hiroshi Ikuta

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Abstract

Highly textured NdFeAs(O,F) thin films have been grown on ion beam assisted deposition (IBAD)-MgO/Y2O3/Hastelloy substrates by molecular beam epitaxy. The oxypnictide coated conductors showed a superconducting transition temperature (Tc) of 43 K with a self-field critical current density (Jc) of 7.0 x 104 A/cm2 at 5 K, more than 20 times higher than powder-in-tube processed SmFeAs(O,F) wires. Albeit higher Tc as well as better crystalline quality than Co-doped BaFe2As2 coated conductors, in-field Jc of NdFeAs(O,F) was lower than that of Co-doped BaFe2As2. These results suggest that grain boundaries in oxypnictides reduce Jc significantly compared to that in Co-doped BaFe2As2 and, hence biaxial texture is necessary for high Jc.

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Kazumasa Iida, Fritz Kurth, Masashi Chihara, Naoki Sumiya, Vadim Grinenko, Ataru Ichinose, Ichiro Tsukada, Jens Hänisch, Vladimir Matias, Takafumi Hatano, Bernhard Holzapfel, Hiroshi Ikuta. 2014-10-31. Highly textured oxypnictide superconducting thin films on metal substrates. https://doi.org/10.1063/1.4900931

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