In situ fabrication of cobalt-doped SrFe₂ As₂ thin films by using pulsed laser deposition with excimer laser

The remarkably high superconducting transition temperature and upper critical field of iron (Fe)-based layered superconductors, despite ferromagnetic material base, open the prospect for superconducting electronics. However, success in superconducting electronics has been limited because of difficulties in fabricating high-quality thin films. We report the growth of high-quality c -axis-oriented cobalt (Co)-doped SrFe₂ As₂ thin films with bulk superconductivity by using an in situ pulsed laser deposition technique with a 248 nm wavelength KrF excimer laser and an arsenic (As)-rich phase target. The temperature and field dependences of the magnetization showing strong diamagnetism and transport critical current density with superior J _c -H performance are reported. These results provide necessary information for practical applications of Fe-based superconductors.