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arXiv · 1102.3506

Quenching of superconductivity by Co doping in K0.8Fe2Se2

Tingting Zhou·Xiaolong Chen·Jiangang Guo·Gang Wang·Xiaofang Lai·Shunchong Wang·Shifeng Jin·Kaixing Zhu
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Abstract

We synthesized a series of K0.8Fe2-xCoxSe2 samples with nominal compositions 0\leq x\leq 0.035 and investigated their physical properties. The results show that the superconductivity in K0.8Fe2-xCoxSe2 is quenched down to 5 K by 0.5 at. % Co doping, the fastest quenching rate ever-reported. The role played here by Co is in contrast with the one in FeAs based superconductors where Co usually induces superconductivity from parent compounds. Such a rapid quenching favors a localized 3d model against the itinerant one for iron pnictide superconductors.

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Tingting Zhou, Xiaolong Chen, Jiangang Guo, Gang Wang, Xiaofang Lai, Shunchong Wang, Shifeng Jin, Kaixing Zhu. 2011-02-17. Quenching of superconductivity by Co doping in K0.8Fe2Se2. https://arxiv.org/abs/1102.3506

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