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

Abstract
Using a combination of pulsed laser deposition and sol-gel processing, we have fabricated epitaxial PbZr0.2Ti0.8O3/YBa2Cu3O7-x heterostructures on single crystalline [001] LaAlO3. Rutherford back-scattering studies show the composition to be the same as the nominal starting composition. Transmission electron microscopy shows the existence of a randomly oriented polycrystalline microstructure in the PZT layer with a grain size of about 500–1000Å. Microscopic pores were also observed in the PZT layer. The PZT film exhibits ferroelectric hysteresis with a saturation polarization of 22–25μC/cm2 (at 7.5V, 1kHz), a remanence of 5–6μC/cm2 and a coercive field of about 40kV/cm.