Enhanced electrocaloric and pyroelectric response from ferroelectric multilayers

Abstract

Room temperature pyroelectric properties and adiabatic temperature change of (001)-textured ferroelectric multilayers on Si are computed by taking into account electrostatic interlayer interactions and thermal strains. We show that by adjusting internal electrical fields through changing relative thicknesses in a multilayer ferroelectric construct, electrothermal properties can be significantly enhanced. A quantitative analysis is provided for BaTiO3-PbZr0.2Ti0.8O3 (BTO-PZT) and SrTiO3-PbZr0.2Ti0.8O3 (STO-PZT) multilayers. For instance, 0.74 × BTO-0.26 × PZT and 0.35 × STO-0.65 × PZT bilayers show ∼120% and 65% increase in electrocaloric response, respectively, compared to PZT films on Si for ΔE = 500 kV/cm.