Exothermic effect of entropy change in second-order phase transition ferroelectrics

Abstract

Abstract Exothermic effect of entropy change by dipole orintation upon E in T-C second order phase transition ferroelectrics is modeled with statistic method. Formula of entropy change and temperature change were derived, showing sharp drop of entropy in higher temperature for higher E, exothermic peak shifts to high temperature with E, and 180° turning of dipole with a critical electric field prevails entropy change in ferroelectric phase, while 180° turning dominates entropy change in paraelectric phase. The results of numerical simulation can explain regulation of heating effect of the ferroelectrics. Morphotropic phase boundary will possess giant exothermic effect in principle.