摘要
本文应用正电子湮没寿命谱方法研究掺杂SrTiO_3陶瓷的介电性.通过对不同掺La量SrTiO_3的介电常数、损耗因子、正电子在样品中的湮没寿命的测量,发现介电常数、损耗因子随掺La量的变化与正电子寿命参量的变化存在着某种关系;文中用Sr空位及La离子与Sr空位缔合体模型解释了这些变化与关系.
The effect of doping on the dielectric property of La-doped SrTiO3 ceramics is studied by the positron lifetime technique. The measurement of the dielectric property shows that with an increase in the La content x (in% mol), the dielectric constant and the tangent of dielectric loss angle (tg) have a peak within the range 0<x<2, and neither changes when x is greater than 2. A positron experiment shows that with an increase of x the lifetime 2 decreases for 0<x<1 and increases for x>l, and the intensity I2 varies oppositely to 2. The positron experiment results show that the concentration of donor La and Sr vacancy increases for 0<x<1, and a complex is formed by La ion and Sr vacancy for x>1. The variation of the dielectric property is explained with the variation of donor La, Sr vacancy and La ion+Sr vacancy complex.
出处
《华中理工大学学报》
CSCD
北大核心
1991年第5期47-51,共5页
Journal of Huazhong University of Science and Technology
基金
煤燃烧国家重点实验室部分资助
关键词
SRTIO3
陶瓷
介电性
掺杂
缔合体
Positron annihilation
SrTiO3 ceramics
Dielectric property
Sr vacancy
Complex
