时间：2025年2月20日（周四）下午14:00-15:30

Time: 14:00-15:30, Thursday, February 20, 2025

主持人: 西湖大学理学院徐水钢博士

Host: Dr. Shuigang Xu, PI of School of Science, Westlake University

地址：西湖大学云谷校区E10-215教室

Venue: Room E10-215, Yungu Campus, Westlake University

语言：中文

Lecture Language: Chinese

Prof. Yu Ye 叶堉

School of Physics, Peking University

主讲人/Speaker:

Yu Ye is a tenured full professor in the School of Physics at Peking University. He received his Ph.D. degree in condensed matter physics from Peking University in 2012. Prior to joining PKU in July 2016, Yu was working as a postdoctoral researcher at the University of California, Berkeley. His research group (http://faculty.pku.edu.cn/yeyu) is currently engaged in studies of light-matter interactions and electrical transport properties in condensed matter physics, with a particular focus on the emergence of novel physical phenomena in atomically thin materials, van der Waals heterostructures, and surfaces/interfaces through nanoscale device designs, low-T-high-B optical spectroscopy, and electrical transport measurements. Yu has published over 100 research papers and has received over 10,000 citations, with an h-index of 46.

摘要/Abstract:

Two-dimensional (2D) magnets decouple from the substrates, allow electrical control, and are mechanically flexible, which collectively facilitate their integration into emerging heterostructures. This integration enables the realization of advanced properties and applications that were previously unattainable. Among these, antiferromagnets are of particular interest for high-speed, low-power spintronics applications due to their terahertz magnetic resonance frequencies, null stray field, vanishing cross-talk between adjacent bits, and robustness against external magnetic field perturbations. However, there is currently no effective method for investigating the magnetic states of the antiferromagnets in the 2D limit due to their atomic thickness and net vanishing magnetization. In this talk, I will present a series of examples demonstrating the use of electrical transport and optical spectroscopy measurements under low temperature and high magnetic field conditions to study the magnetic evolution processes of 2D antiferromagnetic materials down to the monolayer limit. For instance, we have observed the subtle phase transition behavior of exfoliated stripy antiferromagnet CrOCl under varying temperature and magnetic field. This has enabled us to clarify the controversial spin structure of CrOCl under the 2D limit, as well as to elucidate the multiple degrees of freedom coupling of CrOCl. Furthermore, we have uncovered the odd-even layer-number effect and layer-dependent magnetic phase diagrams in A-type antiferromagnet MnBi₂Te₄.

联系人/Contact:

School of Science, Changdan Liao, Email: liaochangdan@westlake.edu.cn