paper

Superconductivity at 35 K by self doping in RbGd $_{2}$ Fe $_{4}$ As $_{4}$ O $_{2}$

arXiv:1606.08161 · doi:10.1088/1361-648X/aa58d2

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 $T_{c}$ = 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 ( $I^¼_{0}$ d $H_{c2}$ /d $T ∣_{T_{c}}$ = 16.5 T/K) is measured for the polycrystalline sample.

10 pages, 6 figures, 1 table, the crystal structure is amended

Superconductivity at 35 K by self doping in RbGd2​Fe4​As4​O2​

Abstract

Superconductivity at 35 K by self doping in RbGd $_{2}$ Fe $_{4}$ As $_{4}$ O $_{2}$