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arXiv · 1201.5201

Superconducting properties and magneto-optical imaging of Ba0.6K0.4Fe2As2 PIT wires with Ag addition

Qing-Ping Ding·Trirat Prombood·Yuji Tsuchiya·Yasuyuki Nakajima·Tsuyoshi Tamegai
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Abstract

We have fabricated (Ba,K)Fe2As2 superconducting wires through ex-situ powder-in-tube method. Silver was used as a chemical addition to improve the performance of these superconducting wires. The transport critical current densities (Jc) have reached 1.3\times104 A/cm and 1.0\times104 A/cm2 at 4.2 K under self field in the wires with and without Ag addition. We used magneto-optical (MO) imaging technique to investigate the properties of grain boundaries in the (Ba,K)Fe2As2 superconducting wire with Ag addition. MO images show the weak links in the Fe-based superconducting wires for the first time. An intragranular Jc of 6.0\times104 A/cm2 at 20 K is obtained from MO image, which is consistent with the estimation from M-H measurement.

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Qing-Ping Ding, Trirat Prombood, Yuji Tsuchiya, Yasuyuki Nakajima, Tsuyoshi Tamegai. 2012-01-25. Superconducting properties and magneto-optical imaging of Ba0.6K0.4Fe2As2 PIT wires with Ag addition. https://doi.org/10.1088/0953-2048%2F25%2F3%2F035019

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