The coexistence of the negative and positive electrocaloric effect in ferroelectric thin films for solid-state refrigeration
Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, Xiangtan University - Hunan Xiangtan 411105, China and Faculty of Materials, Optoelectronics and Physics, Xiangtan University - Hunan Xiangtan 411105, China
Received: 20 March 2013
Accepted: 7 May 2013
The coexistence of the negative and positive electrocaloric effect (ECE) caused by an applied electric field direction different from the dipole direction of 180° domain structures is firstly found in ferroelectric thin films using the phase-field–based simulation. The calculation results reveal that a negative adiabatic temperature change (ΔT = −3.4 K) and a positive adiabatic temperature change (ΔT = 3.1 K) coexist in the PbTiO3 thin film with 180° domain structures under the dimensional electric field ΔE = 0.1. The coexistence of negative and positive ECE in a thin film can provide a new way to design solid-state refrigerators.
PACS: 77.70.+a – Pyroelectric and electrocaloric effects / 77.80.Dj – Domain structure; hysteresis
© EPLA, 2013