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

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. Copyright (C) EPLA, 2016