paper

Superconductivity in KCa $_{2}$ Fe $_{4}$ As $_{4}$ F $_{2}$ with Separate Double Fe $_{2}$ As $_{2}$ Layers

arXiv:1607.01611 · doi:10.1021/jacs.6b04538

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 $I 4/ mmm$ , $a$ = 3.8684(2) Ã , c = 31.007(1) Ã , 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 $_{2}$ .

11 pages, 7 figures, 2 tables

Superconductivity in KCa2​Fe4​As4​F2​ with Separate Double Fe2​As2​ Layers

Abstract

Superconductivity in KCa $_{2}$ Fe $_{4}$ As $_{4}$ F $_{2}$ with Separate Double Fe $_{2}$ As $_{2}$ Layers