清华大学材料科学与工程研究院《材料科学论坛》学术报告
报告时间：2026年4月24日上午10:00-11:30
报告人：Dragan Damjanovic教授（瑞士洛桑联邦理工色播app
）
报告地点：清华大学逸夫技术科学楼A205学术报告厅
邀请人：王轲老师
报告题目：Defect–Domain Wall Interactions in Piezoceramics
报告摘要：
Domain walls are the most important microstructural feature of ferroelectric materials, and their motion—or even their mere presence—can strongly affect material properties. Their interaction with defects is central to their role in determining these properties. Despite its importance, the microscopic understanding of even basic and application-relevant phenomena such as softening and hardening has only relatively recently been clarified.
A key contribution to this understanding has come from extensive theoretical and experimental studies of nonlinear and frequency-dependent domain wall contributions to material properties. In this talk, we will describe and attempt to interpret the frequency- and field-dependent response of various ferroelectric materials, including PZT, BiFeO₃, modified lead titanate, and (Ba,Ca)(Zr,Ti)O₃, where the macroscopic behavior is believed to be governed by interactions between defects and domain walls.
The role of conducting domain walls will also be discussed. Finally, we will consider whether the dynamics of other types of interfaces, such as interphase boundaries, may influence material properties in a manner similar to domain walls. In addition to commonly considered atomic defects or clusters, other types of defects—such as electronic defects, dislocations, and domain–domain interactions—will be addressed. Particular emphasis will be placed on the frequency dependence of the properties, alongside the more commonly studied field-dependent response.
报告人简介：
Dragan Damjanovic earned a BSc diploma in Physics from the Faculty of Natural Sciences and Mathematics at the University of Sarajevo in 1980 and a PhD in Ceramics Science from the Department of Materials Science and Engineering at the College of Earth and Mineral Sciences, Pennsylvania State University (PSU) in 1987.From 1988 to 1991, he worked as a research associate at the Materials Research Laboratory at PSU. In 1991, he joined the Ceramics Laboratory in the Department of Materials Science and Engineering at École Polytechnique Fédérale de Lausanne (EPFL). During his time there, he led the Group for Ferroelectrics and Functional Oxides at the Institute of Materials, and taught undergraduate and graduate courses on the structure and electrical properties of materials. His research focused on fundamental and applied investigations of the piezoelectric, ferroelectric, and dielectric properties of a wide range of materials. He retired from EPFL in March 2022.