Superconductivity
in KCa2Fe4As4F2 with Separate
Double Fe2As2 Layers

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

doi:10.1021/jacs.6b04538.s001

Superconductivity in KCa₂Fe₄As₄F₂ with Separate Double Fe₂As₂ Layers

journal contribution

posted on 2016-06-20, 00:00 authored by Zhi-Cheng Wang, Chao-Yang He, Si-Qi Wu, Zhang-Tu Tang, Yi Liu, Abduweli Ablimit, Chun-Mu Feng, Guang-Han Cao

We report the synthesis, crystal structure, and physical properties of a quinary iron arsenide fluoride, KCa₂Fe₄As₄F₂. The new compound crystallizes in a body-centered tetragonal lattice (space group I4/mmm, a = 3.8684(2) Å, c = 31.007(1) Å, Z = 2) that contains double Fe₂As₂ conducting layers separated by insulating Ca₂F₂ layers. Our measurements of electrical resistivity, direct-current magnetic susceptibility, and heat capacity demonstrate bulk superconductivity at 33 K in KCa₂Fe₄As₄F₂.