Relaxor ferroelectric materials

The authors review relaxor ferroelectrics and associated phenomena and commonalities that materials in this large family share. It is noted that the anomalously large dielectric constants (K) of relaxor ferroelectrics make them ideal for multilayer capacitors, electrostrictive actuators, and E-field-induced piezoelectrics for low-frequency sonar and high-frequency biomedical transducers. The presence of morphotropic phase boundaries in various solid solutions gives rise to a new family of high-K piezoelectrics. Microstructurally, relaxors offer less grain size dependency than normal PZTs, allowing finer scale devices. Commonalities in dielectric and related behavior of relaxors suggest an interrelationship of the underlying intrinsic phenomena of these so-called nanocomposites.