Interfacial charge and strain effects on the ferroelectric behavior of epitaxial (001) PbTiO_3 films on (110) DyScO_3 substrates

摘要

In-situ synchrotron x-ray observations reveal that the ferroelectric behavior of epitaxial (001) PbTiO_3thin films grown on (110) DyScO_3 substrates depends on both film thickness and interfacial electrical properties. A 92-nm-thick film was found to exhibit an a/c domain structure with a ferroelectric Curie temperature similar to that theoretically predicted based on the strain state. In contrast, 6-nm-thick films contained only c-oriented domains, and the ferroelectric behavior was found to depend strongly on the nature of the electrical boundary condition at the buried interface.