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arXiv · 1606.08161

Superconductivity at 35 K by self doping in RbGd$_2$Fe$_4$As$_4$O$_2$

Zhi-Cheng Wang·Chao-Yang He·Si-Qi Wu·Zhang-Tu Tang·Yi Liu·Abduweli Ablimit·Qian Tao·Chun-Mu Feng·Zhu-An Xu·Guang-Han Cao
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Abstract

We report synthesis, crystal structure and physical properties of a novel quinary compound RbGd$_2$Fe$_4$As$_4$O$_2$. The new iron oxyarsenide is isostructural to the fluo-arsenide KCa$_2$Fe$_4$As$_4$F$_2$, both of which contain separate double Fe$_2$As$_2$ layers that are self hole-doped in the stoichiometric composition. Bulk superconductivity at $T_\mathrm{c}$ = 35 K is demonstrated by the measurements of electrical resistivity, dc magnetic susceptibility and heat capacity. An exceptionally high value of the initial slope of the upper critical field ($μ_0$d$H_{\mathrm{c2}}$/d$T|_{T_\mathrm{c}}$ = 16.5 T/K) is measured for the polycrystalline sample.

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Zhi-Cheng Wang, Chao-Yang He, Si-Qi Wu, Zhang-Tu Tang, Yi Liu, Abduweli Ablimit, Qian Tao, Chun-Mu Feng, Zhu-An Xu, Guang-Han Cao. 2016-12-26. Superconductivity at 35 K by self doping in RbGd$_2$Fe$_4$As$_4$O$_2$. https://doi.org/10.1088/1361-648x%2Faa58d2

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