Temperature response features of ferroelectric ceramics in electrocaloric effect study

Temperature response of a material to an external electric field is the main method for electrocaloric effect study in ferroelectrics. In this work, for 0.65PbFe$_{2/3}$W$_{1/3}$O$_{3}$–0.35PbTiO$_{3}$ solid solution as a model object, it is shown that with an increase in the electric field strength, current filamentation effect can occur. It leads to formation of local regions of increased conductivity in the sample. The associated thermal effect have short characteristic times, due to the small volume of the filament. They are comparable to the times of the electrocaloric response of the material, and can lead to significant errors in the detection of the electrocaloric effect.