Role of surface states in polarization reversal of the ferroelectric lead germanate

The present investigation is concerned with the unusual behavior of the uniaxial ferroelectric lead germanate in an external electric field. Lead germanate Pb5Ge3O11 is a collinear (pure) ferroelectric with spontaneous polarization at 20 C. A study was conducted of the repolarization processes in lead germanate. In the experiments, an external electric field was applied to the specimen through external dielectric gaps. Under the considered conditions, complete switching of polarization was observed in constant electric fields up to 18 kV/cm. The dependence of the switching time on the magnitude of the external field is shown in a graph.