Negative/positive elastocaloric effect associated with vortex domain in the Bi₄Ti₃O₁₂ ferroelectric nanoparticle

¹ School of Materials and Engineering, Xiangtan University - Hunan Xiangtan 411105, China
² Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment, Hunan University of Science and Technology - Hunan Xiangtan 411201, China
³ China Three Gorges Corporation - Chengdu, Sichuan 610041, China

^(a) bli@xtu.edu.cn (corresponding author)
^(b) 8010032@hnust.edu.cn (corresponding author)

Received: 17 August 2016
Accepted: 12 September 2016

Abstract

The elastocaloric effect in the Bi₄Ti₃O₁₂(BIT) ferroelectric nanoparticle with vortex domain structure was studied using a phase field simulation in this work. A transformation from the negative elastocaloric effect to positive elastocaloric effect which is associated with vortex domain structure is found under the uniaxial stress in the BIT nanoparticle. In addition, the negative adiabatic temperature change is found under the biaxial compressive stress, and the positive adiabatic temperature change is found under the biaxial tensile stress. The results of this study provide an explanation of the mechanism of the negative/positive elastocaloric effect in the low-dimensional ferroelectrics from the viewpoint of the domain structure.