Influence of epitaxial strain on elastocaloric effect in ferroelectric thin films

Abstract

We report the influence of epitaxial strain um on the elastocaloric properties of BaTiO3 thin films. Using thermodynamic calculations, we show that there exists a critical compressive stress σ3c at which the elastocaloric effect is maximized for any compressive misfit strain we investigate. Moreover, it is found that |σ3c| decreases significantly with decreasing |um| , which is accompanied by a reduction of the elastocaloric response. Interestingly, a several fold enhancement in the electrocaloric effect can be achieved for stress in proximity of σ3c . The elastocaloric effect predicted here may find potential cooling applications by combining the stress-mediated electrocaloric effect or designing hybrid elastocaloric/electrocaloric devices in the future.