报告题目 (Title)：针对界面相变和复杂功能材料的先进透射电子显微镜研究(Probing interface phase transformations and complex functional materials by advanced transmission electron microscopy)
报告人 (Speaker)：Christian Liebscher 教授（波鸿鲁尔大学）
报告时间 (Time)：2025年2月22日（周六）10:00-11:30
报告地点 (Place)：宝山校区 G601
邀请人(Inviter)：任龙
主办部门：量子科技研究院/理学院物理系
报告摘要：
Modern high-performance materials are dominated by an intricate interplay of their atomic structure and internal interfaces. Tailoring materials properties by design is becoming a viable route to establish materials with novel functionalities. However, understanding their underlying atomic nature is a prerequisite to advance material behavior and to ultimately sculpt new materials. Advanced transmission electron microscopy offers unprecedented insights into complex materials and interfaces and is one of the most important tools to establish a fundamental understanding of matter.
In the talk, I will show how aberration-corrected scanning transmission electron microscopy can be used to discover novel interfacial phenomena. A focus will be placed on the observation of grain boundary phase transformations in elemental metals and segregation transitions triggered by solute adsorption at interfaces. By combining atomic resolution imaging and advanced atomistic simulations we explore the underlying nature of the grain boundary phases and obtain novel insights in unexpected interfacial states.
In the reminder of the talk, I will focus on the application of four-dimensional scanning transmission electron microscopy (4D-STEM) to obtain quantitative insights into ferroic oxides. I will show how differential phase contrast 4D-STEM and electron ptychography can be used to uncover novel configurations in NaNbO3 thin films and discuss how they are related to the electrical properties.
