Tohoku University

Abstract：

The introduction of twist engineering to van der Waals (vdW) layers enables the creation of a brand-new moiré system with fascinating properties that never exist in the intrinsic materials [1]. The advent of the family of van der Waals magnets [2] provides the opportunity to artificially tailor the spin degree of freedom through moiré superlattices. I will mainly discuss our recent discovery of moiré magnetism in twisted double bilayer CrI₃. In particular, we have demonstrated voltage-assisted magnetic switching in such moiré magnet devices. The nontrivial magnetic states and unprecedented control by twist angle, temperature, and electrical gating are supported by the simulated phase diagram of moiré magnetism. Additionally, I will give a brief presentation on the emergent phenomena in vdW heterostructures of CrI₃ and CrCl₃, with perpendicular and in-plane magnetic anisotropy, respectively [4]. An interfacial ferromagnetism is demonstrated and can be significantly controlled by a vertical electric field.

References:

[1] E. Y. Andrei et al., Nat. Rev. Mater. 6, 201–206 (2021).

[2] K. S. Burch et al., Nature 563, 47–52 (2018).

[3] G. Cheng et al., Nat. Electron. 6, 434–442 (2023).

[4] G. Cheng et al., Nat. Commun. 13, 7348 (2022).

Brief CV of Dr. Guanghui Cheng:

Dr. Guanghui Cheng is currently an assistant professor at Tohoku University in Japan. He earned both his B.S. and Ph.D. from the University of Science and Technology of China (USTC) (2017), under the supervision of Prof. Changgan Zeng. Following this, he continued his postdoctoral research at the Hong Kong University of Science and Technology with Prof. Jiannong Wang and at Purdue University with Prof. Yong P. Chen. Recently, he got an independent PI position at Tohoku University as a tenure-track assistant professor.

Dr. Cheng’s research interests focus on the coupled quantum states of matter in novel two-dimensional layered heterostructures, particularly in the areas of magnetism and superconductivity. So far, he has published 24 papers in peer-reviewed journals, including 12 first-authored papers on Nat. Electron. (cover story), Phys. Rev. Lett., Nat. Commun., et al. Since joining Tohoku University, he has also received several competitive grants including KAKENHI.

报告地点：M楼253会议室

腾讯会议ID：899-118-781

会议密码：1028

主持人：许杨　特聘研究员

联系人：傅琦（82649469）