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arXiv · 1605.04642

Growth and characterization of CaFe$_{1-x}$Co$_x$AsF single crystals by CaAs flux method

Yonghui Ma·Kangkang Hu·Qiucheng Ji·Bo Gao·Hui Zhang·Gang Mu·Fuqiang Huang·Xiaoming Xie
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Abstract

Millimeter sized single crystals of CaFe$_{1-x}$Co$_x$AsF were grown using a self-flux method. It is found that high-quality single crystals can be grown from three approaches with different initial raw materials. The chemical compositions and crystal structure were characterized carefully. The c-axis lattice constant is suppressed by the Co substitution. Superconductivity with the critical transition $T_c$ as high as 21 K was confirmed by both the resistivity and magnetic susceptibility measurements in the sample with $x$ = 0.12. Moreover, it is found that $T_c$ can be enhanced for about 1 K under the very small hydrostatic pressure of 0.22 GPa, which is more quickly than that reported in the polycrystalline samples. Our results is a promotion for the physical investigations of 1111 phase iron-pnictide superconductors.

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Yonghui Ma, Kangkang Hu, Qiucheng Ji, Bo Gao, Hui Zhang, Gang Mu, Fuqiang Huang, Xiaoming Xie. 2016-05-16. Growth and characterization of CaFe$_{1-x}$Co$_x$AsF single crystals by CaAs flux method. https://doi.org/10.1016/j.jcrysgro.2016.07.029

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