Superconductivity In Epitaxial Thin Films Of Co-doped Srfe_2as_2 With Bilayered Feas Structures And Their Magnetic Anisotropy

摘要

Superconducting epitaxial films of Fe-based layered arsenide, Co-doped SrFe_2As_2, were grown at 700 ℃ on mixed perovskite (La,Sr)(Al,Ta)O_3(001) single-crystal substrates by pulsed-laser deposition. Both the epitaxial film and an (001)-oriented film grown at 600 ℃ exhibited superconducting transitions at ～20K. The zero-resistance states of the epitaxial film were sustained under a magnetic field (H) of 9 T at 9 K when H was parallel to the c-axis, while they were sustained at higher temperatures up to 10 K for H parallel to the a-axis. This is the first demonstration of superconducting thin films of FeAs-based new superconductors.