Superconducting Properties and Phase Diagram of Indirectly Electron-Doped $(hbox{Sr}_{1 - x}hbox{La}_{x})hbox{Fe}_{2}hbox{As}_{2}$ Epitaxial Films Grown by Pulsed Laser Deposition

摘要

A non-equilibrium phase (Sr1-xLax)Fe2As2 was formed by epitaxial film-growth.The resulting films emerged superconductivity along with suppression of theresistivity anomaly that is associated with magnetic and structural phasetransitions. The maximum critical temperature was 20.8 K, which is almost thesame as that of directly electron-doped Sr(Fe1-xCox)2As2. Its electronic phasediagram is much similar to that of Sr(Fe1-xCox)2As2, indicating that thedifference in the electron doping sites does not influence the superconductingproperties of 122-type SrFe2As2.