Large electrocaloric effect in highly (001)-oriented 0.67PbMg 1/3Nb2/3O3-0.33PbTiO3 thin films

(001)-oriented 0.67PbMg1/3Nb2/3O3–0.33PbTiO3 thin films with a pure perovskite crystalline phase were deposited on LaNiO3-coated SiO2/Si substrates by the rf magnetron sputtering technique. We found that the as-grown thin films with (001)-oriented texture possess not only excellent dielectric and ferroelectric properties but also a large electrocaloric effect (14.5 K in 12 V, i.e., 1.21 K/V) which is attributed to the large polarization and entropy change during the ferroelectric–paraelectric phase transition at a high electric field. The discovery of the large electrocaloric effect in highly textured ferroelectric thin films widens their potential applications, such as in solid-state electrical refrigeration.