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arXiv · 1405.6818

Bulk Superconductivity in Fe1+yTe0.6Se0.4 Induced by Removal of Excess Fe

Wei Zhou·Yue Sun·Shuo Zhang·Jincheng Zhuang·Feifei Yuan·Xiong Li·Zhixiang Shi·Tatsuhiro Yamada·Yuji Tsuchiya·Tsuyoshi Tamegai
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Abstract

Experimental evidences from transport, magnetic, and magneto-optical (MO) image measurements confirmed that arsenic (As) vapor annealing was another effective way to induce bulk superconductivity with isotropic, large, and homogenous superconducting critical current density (Jc) in Fe1+yTe0.6Se0.4 single crystal. Since As is an exotic and easily detectable heavy element to Fe1+yTe0.6Se0.4 single crystal, As vapor annealing is very advantageous for the study of annealing mechanism. Detailed micro-structural and elemental analyses exclude the possibility that intercalating or doping effect may happen in the other post-annealing methods, proving that Fe reacts with As on the surface of the crystal and the reaction itself acts as a driving force to drag excess Fe out. The removal of excess Fe results in the good superconductivity performance.

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Wei Zhou, Yue Sun, Shuo Zhang, Jincheng Zhuang, Feifei Yuan, Xiong Li, Zhixiang Shi, Tatsuhiro Yamada, Yuji Tsuchiya, Tsuyoshi Tamegai. 2014-05-27. Bulk Superconductivity in Fe1+yTe0.6Se0.4 Induced by Removal of Excess Fe. https://doi.org/10.7566/jpsj.83.064704

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