Controlling the Magnetic Order in van der Waals Magnets via Moire potential and Spin-Charge Coupling

Layered van der Waals (vdW) magnets have recently emerged as an attractive platform to study and control magnetism in the atomic two-dimensional limit. Here, we particularly highlight that the unique knobs available to the vdw platform—moire potentials and spin-charge coupling—can be exploited to control ground states and excitations of vdw magnets via efficient tuning of the interlayer interactions. First, we show by combining theory and experiments that the ability to tune interlayer interactions via utilizing the twist degree of freedom gives rise to a rich set of non-collinear ground states in twisted double bilayer antiferromagnets [1]. Next, we show theoretically that the dynamical tuning of interlayer interaction via spin-charge coupling [2,3], gives rise to electrically active magnons localized at the topological defects in vdw magnets [4]. These unique control knobs offer a promising route for a broad range of explorations in spintronics and magnetism, such as designing memory, magnon crystals and nanoscale routing of coherent spin information.

[1] Guanghui Cheng, Mohammad Mushfiqur Rahman, Andres Llacsahuanga Allcca, Avinash Rustagi, Xingtao Liu, Lina Liu, Lei Fu, Yanglin Zhu, Zhiqiang Mao, Kenji Watanabe, Takashi Taniguchi, Pramey Upadhyaya, Yong P Chen, Nat. Electronics 6, 434 (2023)

[2] Guanghui Cheng, Mohammad Mushfiqur Rahman, Zhiping He, Andres Llacsahuanga Allcca, Avinash Rustagi, Kirstine Aggerbeck Stampe, Yanglin Zhu, Shaohua Yan, Shangjie Tian, Zhiqiang Mao, Hechang Lei, Kenji Watanabe, Takashi Taniguchi, Pramey Upadhyaya, Yong P Chen, Nat. Comm. 13, 7348 (2022)

[3] Avinash Rustagi, Abhishek Bharatbhai Solanki, Yaroslav Tserkovnyak, and Pramey Upadhyaya, Phys. Rev. B. 102, 094421 (2020)

[4] Mohammad Mushfiqur Rahman, Avinash Rustagi, Yaroslav Tserkovnyak, Pramey Upadhyaya, Phys. Rev. Lett. 130, 036701 (2023)