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arXiv · 1302.4855

Large transport critical currents and magneto-optical imaging of textured Sr1-xKxFe2As2 superconducting tapes

Yanwei Ma·Chao Yao·Xianping Zhang·He Lin·Dongliang Wang·A. Matsumoto·H. Kumakura·Y. Tsuchiya·Y. Sun·T. Tamegai
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Abstract

We report the temperature dependence of the transport critical current density (Jc) in textured Sr1-xKxFe2As2/Fe (Sr122) tapes fabricated by an ex situ powder-in-tube process. Critical currents were measured in magnetic fields up to 0-15 T and/or the temperature range 4.2-30 K by using a dc four-probe method. It was found that textured Sr122 tapes heat-treated at low temperatures showed higher transport Jc performance due to much improved intergrain connections. At temperatures of 20 K, easily obtained using a cryocooler, Jc reached ~ 10^4 A/cm^2 in self field, which is the highest transport value of ferropnictide wires and tapes reported so far. Magneto-optical imaging observations further revealed significant and well distributed global Jc at 20 K in our tapes. These results demonstrate that 122 type superconducting tapes are promising for high-field applications at around 20 K.

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Yanwei Ma, Chao Yao, Xianping Zhang, He Lin, Dongliang Wang, A. Matsumoto, H. Kumakura, Y. Tsuchiya, Y. Sun, T. Tamegai. 2013-02-20. Large transport critical currents and magneto-optical imaging of textured Sr1-xKxFe2As2 superconducting tapes. https://doi.org/10.1088/0953-2048/26/3/035011

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