Electrocaloric Effects in Anti-Ferroelectric PbZrO_3 Thin Films

摘要

Electrocaloric effect (ECE) has recently been attracting attention due to the possible application alternative to the vapor-cycle cooling refrigeration. Usually, external field application orders the electric dipoles and reduces corresponding entropy. Subsequent depolarization randomizes the dipoles and causes an increase of entropy, leading to cool the materials adiabatically. However, recently, unusual “negative” electrocaloric effects have been reported. In this case, the materials cool under electric field and they warm by the field removal. This effects are expected to enhance the cooling efficiency in combination with normal (positive) ECE.