SEMINAR
Shanghai Institute of Ceramics, Chinese Academy of Sciences
中国科学院上海硅酸盐研究所

Relaxor behaviours of complex cubic pyrochlores

Speaker：Dr. Yun Liu，A-professor

Australian Research Council, Queen Elisabeth II Fellow, Future Fellow, Australia

Physical & Mathematical Sciences, Australian National University (ANU), AUSTRALIA

时间：2012年3月29日（星期四）上午10:00 -

地点：二号楼（6楼 - 607会议室）

联系人：李永祥（1066）

Abstracts：Relaxor dielectrics are promising tuneable microwave component materials as a result of the electric field and frequency dependence of their dielectric permittivities. Relaxors of this type have been known for over half a century. The relaxation mechanisms underlying their unique dielectric behaviour, however, are still far from well understood. This lack of understanding provides a significant impediment to the further development and optimization of their desirable dielectric properties (high dielectric constants, low dielectric losses and high field tuneabilities) to meet the demands of the emerging commercial market. Because such relaxors are almost invariably structurally disordered, the key to understand their dielectric properties is an understanding of their local nanoscale crystal structure. In this talk, I will summarize the recent work in our group, introduce two typical local structures in bismuth-based complex cubic pyrochlore systems, discuss the interaction between the local structure and observed dielectric relaxation behaviours..