文摘
Dielectric relaxation properties of the ternary relaxor-based ferroelectric 0.24Pb(In1/2Nb1/2)O3–0.49Pb(Mg1/3Nb2/3)O3–0.27PbTiO3 single crystal have been investigated as a function of temperature (300–570 K) in the frequency range from 100 Hz to 100 kHz. It was found that the variation of the permittivity maximum temperature Tm with frequency obeys the Vogel–Fulcher relationship. The high-temperature (T>Tm) side of the dielectric permittivity deviated from the Curie–Weiss law, but can be described by the Lorenz-type relationship. The coercive field obtained from the polarization hysteresis loops gradually decreases with increasing temperature, and the remnant polarization persists above Tm due to the existence of polar nanoregions (PNRs).