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arXiv · 1101.5427

Enhanced critical current properties in Ba0.6K0.4+xFe2As2 superconductor by over-doping of potassium

Chunlei Wang·Lei Wang·Zhaoshun Gao·Chao Yao·Dongliang Wang·Yanpeng Qi·Xianping Zhang·Yanwei Ma
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Abstract

Phase-pure polycrystalline Ba0.6K0.4+xFe2As2 with were prepared using a one-step solid-state reaction method. We found that over-doping of potassium can improve critical current density (Jc). High-field Jc for samples with x = 0.1 is three times higher than that for samples with x = 0. Over-doping of K has minimal effect on the critical transition temperature (Tc). Less than 0.5 K degradations in Tc was measured for samples with x = 0.1. TEM revealed high concentration of dislocations in samples with x = 0.1, resulting in enhanced flux pining. Further analyses on magnetization loops for powder samples confirm that K over-doping can promote intra-grain Jc. Our results indicate that slight excess of K in Ba0.6K0.4Fe2As2 samples is beneficial to high-field applications.

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Chunlei Wang, Lei Wang, Zhaoshun Gao, Chao Yao, Dongliang Wang, Yanpeng Qi, Xianping Zhang, Yanwei Ma. 2011-01-28. Enhanced critical current properties in Ba0.6K0.4+xFe2As2 superconductor by over-doping of potassium. https://doi.org/10.1063/1.3549195

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