Superconductivity at 35 K by self doping in RbGd2Fe4As4O2.
We report synthesis, crystal structure and physical properties of a novel quinary compound RbGd2Fe4As4O2. The new iron oxyarsenide is isostructural to the fluo-arsenide KCa2Fe4As4F2, both of which contain separate double Fe2As2layers that are self hole-doped in the stoichiometric composition. Bulk superconductivity at [Formula: see text] 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 ([Formula: see text]d[Formula: see text]/d[Formula: see text] [Formula: see text] T K-1) is measured for the polycrystalline sample.
Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China.
Zhi-Cheng
ZC
Wang
Chao-Yang
CY
He
Si-Qi
SQ
Wu
Zhang-Tu
ZT
Tang
Yi
Y
Liu
Abduweli
A
Ablimit
Qian
Q
Tao
Chun-Mu
CM
Feng
Zhu-An
ZA
Xu
Guang-Han
GH
Cao