铁电薄膜的介电性质

基于平均场近似的软模理论,研究了含有表面过渡层的铁电薄膜介电函数的实部ε'和虚部ε″的随温度变化的动态特性。实验结果表明,随着温度的升高ε'和ε″分别出现两个峰和一个峰。当表面过渡层的作用增大时,薄膜的平均介电常数实部和虚部的峰变宽,峰值降低而且峰位向低温区移动。

Dielectric Properties of Ferroelectric Thin Film

Based on the soft mode theory under the mean field approximation,the dynamical behaviors of the temperature dependence of the real(ε ′) and imaginary(ε ″) parts of permittivity of a ferroelectric thin film with surface transition layers have been studied.The results show that with the increase of the temperature,two peaks and one peak of the ε ′ and ε ″ occur,respectively.When the enhance of the action of surface transition layer,the peaks of the real and imaginary parts of the average permittivity of a thin film are broadened,the peak values are declined and the peak positions shift to the lower temperature zone.