湍流与复杂系统国家重点实验室学术报告（报告人：Professor Jiangyu Li）
发布时间: 2009-06-29 12:33:00
SEMINAR SERIES
北京大学工学院 
![]()
力学与空天技术系
湍流与复杂系统国家重点实验室
题目：Mesoscopic Studies of Multiferroic Materials
报告人 Professor Jiangyu Li
Mechanical Engineering, University of Washington Seattle
报告内容摘要
Multiferroics refer to materials with coexistence of multiple ferroic orders, including ferroelasticity, ferroelectricity, and ferromagnetism, making it possible to manipulate the electric state of a multiferroic material by magnetic field, or vice versa, and thus opening a wide range of potential applications in sensing, actuation, data storage, and spintronics. In this talk, we present mesoscopic analyses on the microstructure evolution and macroscopic properties of multiferroic materials. Three case studies will be discussed. The first is the domain switching in ferroelectric ceramics across morphotropic phase boundary (MPB), for which it is demonstrated that mechanical compatibility plays a critical role in determining the polarizibility of ferroelectric ceramics. The second is the magnetic field induced strain in ferromagnetic shape memory alloys, and it is shown that the magnetization rotation leads to substantially smaller strain when the applied compressive stress exceeds a critical values. Finally the magnetoelectric domains and cross-field switching in BiFeO3 films is analyzed, not only confirming the electric control of antiferromagnetic ordering as observed in experiments, but also predicting the mechanical switching of magnetic domains that has not been explored in experiments yet. Some of our recent work on fabrication and characterization of multiferroic nanostructures will also be briefly discussed.
报告人简介
Jiangyu Li is a Bryan T. McMinn Endowed Associate Professor in Mechanical Engineering at University of Washington. Prior joining UW in 2006, He was an Assistant Professor in Engineering Mechanics and a Faculty Fellow at University of Nebraska-Lincoln from 2001 to 2005. He is also a Furong Scholar of Xiangtan University. He obtained Ph.D. in Mechanical Engineering from University of Colorado-Boulder in 1998, and B.S. in Materials Science and Engineering from Tsinghua University in 1994. He did postdoctoral studies at University of California-San Diego and California Institute of Technology from 1998 to 2001. He published over 60 referred journal articles, and has won ASME Best Paper Award in Adaptive Materials and Structures, ICCES Young Investigator Award in Theory, and ASME Sia Nemat-Nasser Early Career Medal.
主持人：方岱宁 教授
时 间: 6月30日（周二）下午3：00
地 点：力学楼434会议室
欢迎广大老师和同学参加！