The electrical properties of epitaxial lead titanate PbTiO3 (PTO) and high
T-c superconductor Y1Ba2Cu3O7-x (YBCO) heterostructures have been studied b
y I-V and C-V techniques. The leakage current is identified to be controlle
d by the combination of Schottky and Frenkel-Poole effects. The dielectric
constant is decreasing with increasing frequency. The loss tan delta is 0.0
51 at a frequency equal to 8200 Hz. Two sharp transition edges are observed
in C-V curves, which we attribute to the domain switching process in the e
pitaxial single crystal PTO layer. (C) 1998 Published by Elsevier Science B
.V. All rights reserved.