Ferroelectric PbZr0.2Ti0.8O3 thin films on epitaxial Y-Ba-Cu-O

We have fabricated epitaxial ferroelectric PbZr0.2Ti 0.8O3/YBa2Cu3O7-x heterostructures on single crystalline [001] LaAlO3. Only the (00l) peaks of the PbZr0.2Ti0.8O3 (PZT) film are observed, indicating that the epitaxial, c-axis oriented YBCO film is a good structural template for the heteroepitaxial growth of PZT films, in addition to being a metallic bottom electrode. A saturation polarization and remanence as high as 38 and 26.5 μC/cm2 (at 7.5 V, 0.5 kHz), respectively, have been achieved. The coercive field is about 100 kV/cm.