| 摘要 |
The purpose of the present invention is to provide an iron-containing superconductive substance comprising an interlayer substance having a low rare earth element content. A superconductive substance which is characterized by being represented by the chemical formula: Ca1-xRxFeAs2, being of a CaFeAs2 type, and having a crystal structure of a space group P21, wherein R represents at least one light rare earth element selected from La, Ce, Pr and Nd and the atomic ratio (x) is 0.08 to 0.24 inclusive (i.e., 0.08 ≤ x ≤ 0.24). The CaFeAs2-type structure is a structure in which a FeAs layer and a Ca1-xRxAs layer are laminated alternately, the Ca1-xRxAs layer comprises a three-layer interlayer substance, i.e., (a Ca1-xRx layer)-(an As2 layer)-(a Ca1-xRx layer), and R is doped to produce the superconductive substance. |
