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arXiv · 1106.3383

Transport properties of the single- and 3-core Fe-Se wires fabricated by a novel chemical-transformation PIT process

Yoshikazu Mizuguchi·Hiroki Izawa·Toshinori Ozaki·Yoshihiko Takano·Osuke Miura
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Abstract

We fabricated single- and 3-core superconducting Fe-Se wires using a novel process based on a chemical transformation from hexagonal FeSe1+d (non-superconducting) to tetragonal FeSe (superconducting) via an optimal supply of Fe from the Fe sheath by annealing. This process enhanced a packing density of superconducting core inside the sheath, owing to an expansion of the lattice volume via a chemical transformation from high-density hexagonal FeSe1+d to low-density tetragonal FeSe. The obtained superconducting wire showed superconductivity below ~10 K and the upper critical field was estimated to be 19.3 T at 0 K. The obtained transport critical current densities at 0 T were 588 A/cm2 for the 3-core wire and 218 A/cm2 for the single-core wire.

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Yoshikazu Mizuguchi, Hiroki Izawa, Toshinori Ozaki, Yoshihiko Takano, Osuke Miura. 2011-06-17. Transport properties of the single- and 3-core Fe-Se wires fabricated by a novel chemical-transformation PIT process. https://doi.org/10.1088/0953-2048%2F24%2F12%2F125003

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