报告题目Title：Slush Structure and Dynamics in a Relaxor Ferroelectric 弛豫铁电材料的结构和动力学
报 告 人Speaker：Andrew M. Rappe教授（University of Pennsylvania 宾州大学）
报告时间Time：2016年12月28日(周三) 10:00
报告地点Venue：校本部E106（上海大学量子与分子结构国际中心SHU ICQMS）
摘要：Ferroelectrics are smart functional materials that interconvert electrical and mechanical energy. As such, they are the functional components of SONAR, ultrasound, smart cards, transducers, and actuators. Ferroelectric materials undergo solid-solid structural phase transitions between phases with aligned dipoles and randomly oriented dipoles.
Incorporating quenched Coulombic disorder by varying the charge of the ions on the lattice disrupts and changes the character of this transition; instead of a sharp transition in a small temperature range, these oxide alloys exhibit "relaxed" transition
over 100-200 K and are called "relaxor ferroelectrics." In this talk I will describe how a first-principles based multi-scale model can reveal the dynamic and statically correlated motions of ions that lead to relaxor behavior, and I will discuss their promise for next-generation piezoelectric and dielectric material systems.
