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arXiv · 1607.01611

Superconductivity in KCa$_2$Fe$_4$As$_4$F$_2$ with Separate Double Fe$_2$As$_2$ Layers

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

We report synthesis, crystal structure and physical properties of a quinary iron-arsenide fluoride KCa$_2$Fe$_4$As$_4$F$_2$. The new compound crystallizes in a body-centered tetragonal lattice (with space group $I4/mmm$, $a$ = 3.8684(2) Å, c = 31.007(1) Å, and $Z$ = 2), which contains double Fe$_2$As$_2$ conducting layers separated by insulating Ca$_2$F$_2$ layers. Our measurements of electrical resistivity, dc magnetic susceptibility and heat capacity demonstrate bulk superconductivity at 33 K in KCa$_2$Fe$_4$As$_4$F$_2$.

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Zhi-Cheng Wang, Chao-Yang He, Si-Qi Wu, Zhang-Tu Tang, Yi Liu, Abduweli Ablimit, Chun-Mu Feng, Guang-Han Cao. 2016-07-06. Superconductivity in KCa$_2$Fe$_4$As$_4$F$_2$ with Separate Double Fe$_2$As$_2$ Layers. https://doi.org/10.1021/jacs.6b04538

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