Upper critical fields and critical current density of BaFe2(As0.68P0.32)2 single crystal

S V Chong; S Hashimoto; K Kadowaki

doi:10.1016/j.ssc.2010.04.019

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arXiv · 0908.3284

Upper critical fields and critical current density of BaFe2(As0.68P0.32)2 single crystal

S V Chong·S Hashimoto·K Kadowaki

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Abstract

The transport properties, upper critical fields, superconducting anisotropy, and critical current density in an iso-valent phosphorus-doped BaFe2As2 single crystal close to optimum doping are investigated in this report. Temperature dependent resistivity and susceptibility show a superconducting transition temperature, Tc, just below 31 K both with sharp transitions. The upper critical field parallel to the ab-plane, Hc2^ab, is above 77 Tesla while that along the c-axis direction, Hc2^c, is just above 36 Tesla, yielding a low superconducting anisotropy ratio ~ 2. The estimated inter-plane coherence length based on the Ginzburg-Landau (G-L) theory indicates BaFe2(As0.68P0.32)2 is still above the point for a dimensional crossover inferring the superconducting layers are not weakly-coupled in this system. The critical current density at 5 K obtained from magnetization loops measurement show a modest Jc as high as 10^5 A/cm2.

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S V Chong, S Hashimoto, K Kadowaki. 2010-05-30. Upper critical fields and critical current density of BaFe2(As0.68P0.32)2 single crystal. https://doi.org/10.1016/j.ssc.2010.04.019

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