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

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 YBa₂Cu₃O_7-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.