Pyroelectric Properties of Epitaxial (001) Barium Strontium Titanate as a Function of Space Charge Density

摘要

A non-linear thermodynamic model was developed to investigate the effect of charge compensation on polarization and pyroelectric properties of graded monodomain ferro-electric multilayers. To represent charge compensation at the interfaces, a dimensionless parameter, "coupling strength," was introduced. Heterostructures in which interfaces are perfectly insulating so that coupling strength is maximized behave as if they are a single ferroelectric material. Upon introduction of localized space charges to the interfaces, the coupling strength is decreased and ferroelectric layers behave independently of each other. Also, there exists an optimum value of the coupling strength at which average polarization of the heterostructure is maximized.