学术报告：Topological Vortex Domains in Quantum Materials
报告人: Sang-Wook Cheong 教授（美国罗格斯大学）
时间: 12月17日（周一），下午2:00
地点: 田家炳楼南203室
邀请人：董帅。欢迎参加！
报告人简介：国际著名材料物理学家，罗格斯大学 Board of Governors教授, Henry Rutgers教授，量子材料合成中心创始主任、罗格斯新兴材料中心创始主任。美国物理学会会士、美国物理学会James C. McGroddy奖获得者，韩国Ho-am奖获得者。曾任PRL部门副主编，现任Npj Quant. Mater.主编。本科毕业于韩国首尔大学、博士毕业于加州大学洛杉矶分校。曾在洛斯阿拉莫斯国家实验室、贝尔实验室从事研究工作。在牛津大学、东京大学等多所国际知名大学任访问教授。发表论文700余篇，其中Nature/Science 10篇，PRL130余篇，引用46500余次，其中6篇单篇引用过1000次，H指数102。2003年WoS全球高被引物理学家第13名。
报告摘要：Engineering of domains and domain boundaries is quintessential for technological exploitation of numerous functional materials. However, it has only recently realized that the configuration of these domains/domain boundaries can have non-trivial topology. We will discuss a new topological classification scheme of domain/domain boundary configurations with Ising-type or two-dimensional order parameters: Zm×Zn domains (m directional variants and n translational antiphases) and Zl vortices (where l number of domains and that of domain boundaries merge). This classification, with the concept of topological protection and topological charge conservation, has been applied to a wide range of materials such as improper ferroelectric R(Mn,Fe)O3, antipolar In(Mn,Ga)O3, hybrid improper ferroelectric (Ca,Sr)3Ti2O7, chiral (and ferromagnetic) Fe1/3TaS2, magnetic-superconducting Sr2VO3FeAs, magnetic a-Fe2O3, and CDW systems such as 2H-TaSe2. We will also discuss the emergent physical properties of domain boundaries, distinct from those of domains. The presented topological consideration provides a basis in understanding the formation, kinetics, manipulation and property optimization of domains/domain boundaries in quantum materials.