The effect of out-of-plane strain on the electrocaloric performances of P(VDF-TrFE) vertical heteroepitaxial film

Considering the boundary conditions of 1-3-type P(VDF-TrFE) composite ferroelectric film, the effect of out-of-plane strain on the electrocaloric performances of vertical heteroepitaxial film is calculated by the nonlinear thermodynamic theory. The results indicate that the out-of-plane strain can effectively regulate the ferroelectric and electrocaloric performances including the polarization, electrocaloric coefficient and adiabatic temperature change under the action of vertical electric field. In a wide temperature range, the vertical heteroepitaxial film can present higher adiabatic temperature change than the pure P(VDF-TrFE) film by controlling the out-of-plane strain. This indicates that the vertical composite heteroepitaxial film with excellent electrocaloric performances will have potential applications in the microelectronic devices such as micropowers, optical communication diodes and infrared sensors.