Indirect and Direct Measurements of the Electrocaloric Effect

Abstract

Two types of indirect measurements of the EC effect will be described. In the first method the EC change of temperature is calculated from measurements of the field and the temperature dependence of the polarization P(T,E). In the second, by phenomenological approach the entropy change is calculated by expanding the entropy in a power series of polarization. The EC entropy change is then calculated by performing two sets of experiments. In the first set the leading coefficients in the expansion are determined via linear and nonlinear dielectric spectroscopy. In the second set, the P(T,E) is determined. Possible shortcomings and the problems related to the above, indirect methods will be discussed.