Superconductivity in epitaxial thin films of Co-doped SrFe 2As2 with bilayered FeAs structures and their magnetic anisotropy

Abstract

Superconducting epitaxial films of Fe-based layered arsenide, Co-doped SrFe2As2, were grown at 700°C on mixed perovskite (La,Sr)(AI,Ta)O3(OOI) single-crystal substrates by pulsed-laser deposition. Both the epitaxial film and an (001)-oriented film grown at 600°C 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. © 2008 The Japan Society of Applied Physics.