Giant electrocaloric effect at the antiferroelectric- to-ferroelectric phase boundary in Pb(Zr_xTi_(1-x))O_3

摘要

Molecular dynamics simulations predict a giant electrocaloric effect at the ferroelectric-antiferroelectric phase boundary in PZT (PbTiO3-PbZrO3). These large-scale simulations also give insights into the atomistic mechanisms of the electrocaloric effect in Pb(ZrxTi1-x)O-3. We predict a positive electrocaloric effect in ferroelectric PZT, but antiferroelectric PZT exhibits a negative-to-positive crossover with the increasing temperature or electric field. At the antiferroelectric-to-ferroelectric phase boundary, we find complex domain patterns. We demonstrate that the origin of the giant electrocaloric change of temperature is related to the easy structural response of the dipolar system to external stimuli in the transition region.