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arXiv · 0809.2009

Superconductivity induced by Ni doping in BaFe$_2$As$_2$

L. J. Li·Q. B. Wang·Y. K. Luo·H. Chen·Q. Tao·Y. K. Li·X. Lin·M. He·Z. W. Zhu·G. H. Cao·Z. A. Xu
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Abstract

A series of 122 phase BaFe$_{2-x}$Ni$_x$As$_2$ ($x$ = 0, 0.055, 0.096, 0.18, 0.23) single crystals were grown by self flux method and a dome-like Ni doping dependence of superconducting transition temperature is discovered. The transition temperature $T_c^{on}$ reaches a maximum of 20.5 K at $x$ = 0.096, and it drops to below 4 K as $x$ $\geq$ 0.23. The negative thermopower in the normal state indicates that electron-like charge carrier indeed dominates in this system. This Ni-doped system provides another example of superconductivity induced by electron doping in the 122 phase.

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L. J. Li, Q. B. Wang, Y. K. Luo, H. Chen, Q. Tao, Y. K. Li, X. Lin, M. He, Z. W. Zhu, G. H. Cao, Z. A. Xu. 2008-12-22. Superconductivity induced by Ni doping in BaFe$_2$As$_2$. https://doi.org/10.1088/1367-2630%2F11%2F2%2F025008

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