Abstract
Temperature dependence of ferroelectric domain nucleation in epitaxial films of BiFeO3 was studied using variable temperature ultra-high vacuum piezoresponse force spectroscopy in the 50 - 300 K temperature range. The nucleation bias corresponding to the onset of local ferroelectric switching in the volume of electrostatic field confined by the metal tip was found to be less than 20% change across the whole temperature range. Combination of the analytical and phase-field analysis proves that the weak temperature dependence of nucleation bias is a hallmark of the intrinsic, rather than thermally activated, nucleation mechanism. The effect of disorder on the observed distribution of the nucleation bias between vacuum and ambient environments is compared.
