Polar state in epitaxial films of the relaxor ferroelectric PbMg1/3Nb2/3O3 -: art. no. 224101

Dielectric response of epitaxial thin films of relaxor PbMg1/3Nb2/3O3 was experimentally studied as a function of frequency, temperature, amplitude of ac electric field, and magnitude of dc bias. At small fields, a glass-like relaxor behavior was observed. With increasing field, an onset of a polar state was detected. Compared to bulk, such an onset was characterized by relatively low threshold fields, short critical time, and reversibility. The orientation of the polar clusters along the direction of the field and the low energy barriers between the stable states of the clusters were suggested to be responsible for the onset.