缺陷钉扎导致的铁电陶瓷介电弛豫  

Dielectric Relaxation in Ferroelectric Ceramics Induced by Defect Pining

作　　者：李立本[1,2] 郭惠芬[1] 陈庆东[1] 李庆收[1] 

机构地区：[1]河南科技大学物理与工程学院,河南洛阳471023 [2]南京大学固体微结构物理国家重点实验室,江苏南京210093

出　　处：《河南科技大学学报（自然科学版）》2012年第5期93-96,10,共4页Journal of Henan University of Science And Technology:Natural Science

基　　金：国家自然科学基金项目(50972056);南京大学固体微结构物理国家重点实验室开放基金项目

摘　　要：把电荷密度波理论引入到铁电陶瓷的介电温谱研究中。指出陶瓷中缺陷的钉扎效应导致介电响应的弛豫。高温时,集体钉扎主导陶瓷的极化行为;低温时,局域亚稳态的弛豫对极化起决定作用。两者的竞争导致介电峰值的出现。理论计算与试验结果定性吻合。Unlike the pure ferroelectric ceramics,doped ferroelectric ceramics shows a regular dielectric relaxation characteristic.The charge-density-waves theory was introduced into the study of the dielectric temperature spectrum of ferroelectric ceramics.It was pointed out that the pinning effect of defects in the ceramics answers for the dielectric relaxation.The polarization behavior of the ceramics is mainly dominated by the collective pinning at high-temperature and by the relaxation of the local meta-stable at low temperature.The competition between the collective and local pinning leads to the emergence of the dielectric peak.Theoretical calculations are qualitatively consistent with the experimental results.

关 键 词：铁电陶瓷 介电弛豫 电荷密度波 缺陷钉扎 介电峰值温度 

分 类 号：O484[理学—固体物理]