PZT四方相区介电常数ε_r与晶格畸变关系的研究

Study on the relation between the dielectric properties and lattice distortions in PZT ferroelectric tetragonal phase region

从Haun的PZT热力学理论出发 ,给出了PZT四方相区介电常数εr 与晶格畸变c a关系的基本方程 ,并深入地根据相关实验资料和物理图像的合理推论 ,建立了关于晶格畸变c a与介电常数εr 相互依赖的基本关系式 .然后 ,根据该基本关系式仔细地研究了PZT四方相区晶格畸变c a对介电常数εr 影响的物理图像 .与相关实验资料比较表明 ,基本关系式得到的介电常数εr 随晶格畸变c a的变化规律 ,与相关实验结果相比较 ,两者吻合得很好 .最后并对该基本关系式的适用范围 ,和范围以外存在的相对偏差产生的物理原因进行了讨论 .必须强调指出 ,本文建立的基本关系式实质上适用于所有四方相区钙钛矿结构材料晶格畸变对介电常数影响 .

From thermodynamic theory of the lead zirconate-titanate(PZT) solid solution system, we have got the basic equation between the dielectric constant ε r and lattice distortion c/a in ferroelectric tetragonal phase region, and based on the relative experimental data and logical deduction to physics image, we have established basic relations between ε r and c/a. And then, from the basic relations, we have studied in detail the physics image about lattice distortion c/a effect on the dielectric constant ε r in ferroelectric tetragonal phase region. A comparison with related experimental results indicates that the results of the basic relations are in good agreement with the conclusions of the experiments. Finally, we have discussed the application range of the basic relations and the physics reason of relative warp out of application range. We would emphasize that the basic relations are essentially fitted to all perovskite structure materials.