摘要
建立组分梯度铁电薄膜的理论模型,在唯象理论GLD的框架下,引入一个分布函数描述组分梯度的特性,通过改变相关参数、薄膜的厚度及外电场等因素,研究了组分梯度铁电薄膜的热释电性质.结果表明:组分的梯度分布造成了薄膜内极化强度的梯度分布;相关参数和薄膜厚度是影响铁电薄膜性质的2个重要因素;当施加外电场的方向与薄膜内各组分极化方向相反时,薄膜的平均极化强度和温度的关系呈现出类似一级相变的特性,这一现象对薄膜的热释电性质会造成影响.
Theoretical model for component-graded ferroelectric thin films is set up.In the framework of the Ginzburg-Landau-Denvonshire（GLD） theory,a distribution function is introduced to characterize the properties of graded components.With the variation of related parameter,film thickness and external electric field,the pyroelectric properties of component-graded ferroelectric thin films are mainly discussed.It ’ s shown that the component gradient leads to the graded-polarization distribution in films.The related parameter and films thickness are two main factors to inflence the films properties.When the direction of the external electric field is opposite to the polarizations of components,the average polarization vs temperature curves present first-order phase transition type,which may have influence on film pyroelectric properties.
出处
《河北师范大学学报（自然科学版）》
CAS
北大核心
2012年第6期573-576,共4页
Journal of Hebei Normal University：Natural Science
基金
国家自然科学基金(10647138)
辽宁省科研基金(L2012136)
关键词
铁电薄膜
组分梯度
热释电系数
唯象理论
相变温度
ferroelectric thin film
component gradient
pyroelectric coefficient
phenomenological theory
phase transition temperature
