主持人：郑海标 副教授
报告时间：2020年7月29日下午15:00- 16:00
报告平台：Zoom会议 房间号：924 6976 5319 密码 123456

报告人介绍：包维柱，新加坡国立大学数学系教授。1992年清华大学，学士,1995年清华大学，博士。随后在清华大学数学科学系工作，历任讲师、副教授。2001年起在新加坡国立大学工作，2005年晋升为终身副教授，2009年晋升为教授，担任该校数学系provost’s讲座教授。2013年获得第十届冯康科学计算奖。2014年，在韩国举行的第26届国际数学家大会上作45分钟邀请报告。包维柱教授主要从事科学与工程计算研究，涉及偏微分方程数值方法及其在量子物理、流体和材料中的应用。

报告内容摘要：In this talk, I present sharp interface models with anisotropic surface energy and a phase field model for simulating solid-state dewetting and the morphological evolution of patterned islands on a substrate in two and three dimensions.

We show how to derive the sharp interface model via thermovariation dynamics, i.e. variation of the interfacial energy via an open curve with two triple points moving along a fixed substrate. The sharp interface model tracks the moving interface explicitly and it is very easy to be handled in two dimensions via arc-length parametrization. The phase field model is governed by the Cahn-Hilliard equation with isotropic surface tension and variable scalar mobility and it easily deals with the complex boundary conditions and/or complicated geometry arising in the solid-state dewetting problem. Since the phase field model does not explicitly track the moving surface, it naturally captures the topological changes that occur during film/island morphology evolution. Efficient and accurate numerical methods for both sharp interface models and phase field models are proposed. They are applied to study numerically different setups of solid-state dewetting including short and long island films, pinch-off, hole dynamics, semi-infinite film, etc. Our results agree with experimental results very well. This talk is based on joint works with Wei Jiang, David J. Srolovitz, Carl V. Thompson, Yan Wang and Quan Zhao.