哈尔滨工业大学（深圳）学术讲座

(有学术小票)

演讲人Speaker：戴俊峰(Jun-Feng Dai)

题目Title: 2D magnetic materials and the controlling of magnetic properties by external forces

时间Date： 2024 年 3 月 29 日       Time：10:30-11:30

地点Venue： H栋311室

内容摘要Abstract： 

The research on van der Waals (vdW) layered ferromagnets has promoted the development of nanoscale spintronics and applications. However, the Mermin-Wagner-Coleman theorem predicts no long-range magnetic order at finite temperature in the two- dimensional (2D) isotropic systems, but it does predict a quasi-long-range order with a divergent correlation length at the Kosterlitz-Thouless (KT) transition for planar magnets. In this talk, with the aid of magnetostriction which is sensitive to the local magnetic order, we experimentally observed the quasi-long-range order in an exact 2D planar spin model – monolayer CoPS3, below KT phase transition[1]. Moreover, the control of magnetic properties in 2D magnets is another interesting topic in the field of 2D materials. Hence, in the second part of this talk, I will focus on how to achieve the tunability of ferromagnetic properties in layered magnets, such as CrSiTe3[2] and VI3[3] by an external force. The effective interaction between magnetic couplings and external force offers new opportunities in pursuit of layered ferromagnets with high curie temperature and strong coercivity.

[1] Q. Liu et al., Physical Review B 103, 235411 (2021).

[2] C. Zhang et al., Nano Letters 21, 7946 (2021).

[3] X. Zhang et al., Nano Letters 22, 9891 (2022).

个人简介(About the speaker):

Jun-Feng Dai got his Ph.D. in condensed matter physics from the University of Hong Kong, and now is an Associate Scientist at the Institute for Quantum Science and Engineering, SUSTech. His research primarily focuses on magnetic orders in two-dimensional materials down to the monolayer limit and force-controlled ferromagnetic and antiferromagnetic properties in 2D magnets. He has published around 30 papers in prestigious journals including Nature Nanotechnology, Physics Review Letters, Nano letters, etc.