As-grown preparation of high-critical-temperature superconducting Y1Ba2Cu3O7−x films by radio-frequency plasma flash evaporation

Publisher Website
Google Scholar
Abstract
As‐grown superconducting Y1Ba2Cu3O7−x films were successfully synthesized on (100) MgO and (100) SrTiO3 substrates by radio‐frequency (rf) plasma flash evaporation, in which fine powder mixtures of constituents are continuously injected into an rf plasma, co‐evaporated, and co‐deposited onto a substrate. In particular, films deposited on a (100) SrTiO3 substrate at 670 °C exhibited a superconducting transition temperature Tc of 92 K and critical current density Jc of 3×105 A/cm2 under zero magnetic field at 77 K. The excitation temperatures of several species during the depositions were estimated from optical emission spectroscopy. The temperature of Y+ was a few thousand degrees lower than that of Ba+ and Cu. The difference in these excitation temperatures revealed that this plasma process was a nonequilibrium deposition.