Study of defect-dipoles in an epitaxial ferroelectric thin film

We have analyzed the defect contributions to the in-plane polarization switching of epitaxial (001) BiFeO3 thin films on (110) TbScO3 substrates. Interdigitated electrodes were patterned with respect to ferroelectric stripe domains in the BiFeO3 film. Polarization measurements exhibited a clear double hysteresis caused by the presence of a static defect field (similar to 40 kV/cm); the field resulted from ordered defect-dipoles initially aligned to the spontaneous polarization. By monitoring the defect field, both realignment and disassociation of the defect-dipoles were demonstrated. These results establish the arrangement of defect-dipoles in epitaxial ferroelectric thin films, guiding technologies and opening an avenue for defect related studies.