Epitaxial CeO2 films as buffer layers for high-temperature superconducting thin films

Abstract
We have prepared epitaxial (100)CeO2 thin films on LaAlO3, sapphire, and yttria‐stabilized zirconia using pulsed laser deposition. It is demonstrated in this letter that the CeO2 films are chemically and structurally compatible to the high‐temperature superconductor YBa2Cu3O7−δ (YBCO). Epitaxial YBCO films on CeO2/LaAlO3 had a zero resistance temperature and critical current density in a zero field of 90 K and 5.9×106 A/cm2 at 75 K, respectively. Furthermore, epitaxial multilayers of CeO2/YBCO were prepared. This work demonstrated that CeO2 is an excellent buffer layer material for the high‐temperature superconductors.