Highly c-axis orientated superconducting core and large critical current density in Ba0.6Na0.4Fe2As2 powder-in-tube tape

S Imai; S Itou; S Ishida; Y Tsuchiya; A Iyo; H Eisaki; K Matsuzaki; T Nishio; Y Yoshida

doi:10.1038/s41598-019-49363-y

Highly c-axis orientated superconducting core and large critical current density in Ba_0.6Na_0.4Fe₂As₂ powder-in-tube tape

Sci Rep. 2019 Sep 10;9(1):13064. doi: 10.1038/s41598-019-49363-y.

Authors

S Imai^{1

2}, S Itou^{3

4}, S Ishida⁵, Y Tsuchiya⁴, A Iyo⁴, H Eisaki⁴, K Matsuzaki⁴, T Nishio⁶, Y Yoshida⁴

Affiliations

¹ Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo, 162-8601, Japan. s.imai@aist.go.jp.
² National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan. s.imai@aist.go.jp.
³ Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo, 162-8601, Japan.
⁴ National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan.
⁵ National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568, Japan. s.ishida@aist.go.jp.
⁶ Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo, 162-8601, Japan. nishio@rs.kagu.tus.ac.jp.

Abstract

Improvement of the critical current density (J_c) of superconducting wires/tapes is one of the key issues in the field of superconductivity applications. Here we report the fabrication of a silver-sheathed Ba_1-xNa_xFe₂As₂ (BaNa-122) superconducting tape by using a powder-in-tube technique and its superconducting properties, in particular transport J_c, as well as the tape-core texture. The optimally-doped BaNa-122 tape with Na concentration x = 0.4 exhibits the superconducting critical temperature (T_c) of 33.7 K and high transport J_c of 4 × 10⁴ A/cm² at 4.2 K in a magnetic field of 4 T. Patterns of x-ray diffraction for the superconducting core show that the degree of c-axis orientation is significantly enhanced through the tape fabrication process. The tendency of c-axis orientation is advantageous for achieving higher J_c, suggesting the high potential of BaNa-122 for superconducting wire/tape applications.