Low-temperature piezoresponse force microscopy on barium titanate

Piezoresponse force microscopy (PFM) is a well-established method to study ferroelectric domains on the nanometer length scale. Here, we apply low-temperature PFM and Kelvin probe force microscopy (KPFM) to investigate the domain configuration of (111)-oriented barium titanate in the temperature range from 150 K to 290 K. We are able to identify all three ferroelectric phases and domain orientations from the combined PFM, KPFM, and topographic data. Ferroelectric phase transitions manifest in changes of the piezoelectric tensor elements as well as in variations of the spatial domain arrangement. A complete reordering of domains occurs exclusively upon the rhombohedral-to-orthorhombic phase transition during heating.