摘要
用正电子湮没寿命谱技术对有意掺杂的或被杂质替代的钙钛矿结构压电陶瓷中的点缺陷进行了研究．掺杂了Ｌａ３＋的ＰｂＴｉＯ３，掺杂了Ｓｒ２＋，Ｃｄ２＋和Ｌａ３＋的Ｐｂ（Ｍｇ１／３Ｎｂ２／３）０３７５Ｔｉ０３７５Ｚｒ０２５Ｏ３，掺杂了Ｃａ２＋的ＢａＴｉＯ３和掺杂了Ｎｂ５＋的ＳｒＴｉＯ３为试验材料．研究发现，正电子会被阳离子空位、氧空位以及晶格形变等多种缺陷俘获．但正电子被这些缺陷俘获的动力学正电子比俘获率以及正电子在缺陷中的湮没特性因缺陷种类而异．提出了一种测定钙钛矿结构压电陶瓷中的点缺陷种类的正电子寿命谱方法．
Abstract A systematic investigation of different types of lattice defects in intentionally doped or impurity substituted piezoelectric ceramics was carried out by using positron annihilation.La 3+ doped PbTiO 3,Sr 2+ ,Cd 2+ ,and La 3+ doped Pb (Mg 1/3 Nb 2/3 ) 0 375 Ti 0 375 Zr 0 25 O 3;Ca 2+ doped BaTiO 3; and Nb 5+ doped SrTiO 3 were chosen as testing materials.It was found that positrons can be traped by cation vacancies,oxygen vacancies,as well as defects associated with lattice deformations,but with different dynamic specific trapping rates and annihilation characteristics.A new possible method for determining the defect species in perovskite structured piezoelectric ceramics is presented.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
1998年第1期146-153,共8页
Acta Physica Sinica
基金
国家自然科学基金
