Relaxor and incipient ferroelectric phases in 6.5/65/35 PLZT ceramics

The linear and third harmonic nonlinear dielectric constants were measured in 6.5/65/35 PLZT hot-pressed ceramics. Linear dielectric data obtained on ooling show the transition from an ergodic to a nonergodic relaxor phase while, on heating, a ferroelectric to ergodic relaxor phase transition appears. The third harmonic di-electric response is reminiscent of an ergodic to nonergodic relaxor phase transition. Existence of the spontaneous polarization below the Vogel–Fulcher temperature at which the longest relaxation time diverges, indicates the possibility that the sample breaks up at low temperatures into relaxor glass-like and ferroelectric order dominated regions.