Indentation induced local polarization reversal in La doped BiFeO3 ceramics

Stress-induced local polarization reversal was studied in La doped
BiFeO3 ceramics under the action of Berkovich-type prism indentation.
Piezoresponse force microscopy was used for detailed study of
domain structure before and after local polarization reversal. Two
mechanisms of domain formation under the action of the mechanical
loading were revealed: (1) direct stress-induced and (2) stress
mediated by grain clamping. Critical stress value for local polarization
reversal was extracted from the dependence of the switched
area on the applied loading force