Voltage-dependent domain evolution in La0.89Sr0.11MnO3 single crystals by Piezoresponse Force Microscopy

Bias voltage dependent domain dynamics have been investigated on the surface of La0.89Sr0.11MnO3 (LSMO-0.11) single crystals by Piezoresponse Force Microscopy (PFM). The created domain size increases with both the amplitude and duration of the bias voltage pulse. It is observed that domain growth takes place following an activated process wherein the domain wall interacts with the defects (e.g. oxygen vacancies) resulting from the high electric field under the PFM tip. Fractal analysis, based on the interaction of the domain boundary with the defects, provides the Hausdorff fractal dimension value ∼1.3, lower than that usually observed for solid-state crystalline ferroelectrics indicating a smaller correlation length value for LSMO-0.11 crystal. These studies reveal a clear potential of LSMO for new memory devices based on ferroelectric-like domain states in manganites.