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arXiv · 1409.6402

The effect of Cr impurity to superconductivity in electron-doped BaFe2-xNixAs2

Rui Zhang·Dongliang Gong·Xingye Lu·Shiliang Li·Pengcheng Dai·Huiqian Luo
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Abstract

We use transport and magnetization measurements to study the effect of Cr-doping to the phase diagram of the electron-doped superconducting BaFe2-xNixAs2 iron pnictides. In principle, adding Cr to electron-doped BaFe2-xNixAs2 should be equivalent to the effect of hole-doping. However, we find that Cr doping suppresses superconductivity via impurity effect, while not affecting the normal state resistivity above 100 K. We establish the phase diagram of Cr-doped BaFe2-x-yNixCryAs2 iron pnictides, and demonstrate that Cr-doping near optimal superconductivity restore the long-range antiferromagnetic order suppressed by superconductivity.

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Rui Zhang, Dongliang Gong, Xingye Lu, Shiliang Li, Pengcheng Dai, Huiqian Luo. 2014-09-23. The effect of Cr impurity to superconductivity in electron-doped BaFe2-xNixAs2. https://doi.org/10.1088/0953-2048%2F27%2F11%2F115003

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