Size and interface effects on Curie temperature of perovskite ferroelectric nanosolids

摘要

A simple and unified model, without any adjustable parameter, is established for size effect on Curie temperature of low-dimensional ferroelectrics (thin films, nanowires and nanoparticles), T c(D), where D denotes size of low-dimensional ferroelectrics. T c(D) function is based on consideration on the size dependence of spontaneous polarization of low-dimensional ferroelectrics P s(D), which is determined by the misfit strain at the ferroelectrics/substrate interface. It is shown that P s(D) and T c(D) functions decrease or increase when the misfit strain is tensile or compressive. The numerically predicted results are in agreement with the available experimental results of BaTiO3 and PbTiO3 nanoparticles and thin films.