Atomically flat surfaces of van der Waals (vdW) materials pave an avenue for addressing a long-standing fundamental issue of how a perfectly compensated antiferromagnet (AFM) surface frustrates a ferromagnetic (FM) overlayer in FM/AFM heterostructures. By revealing the AFM and FM spin structures separately in vdW Fe5GeTe2/NiPS3 heterostructures, we find that C-type in-plane AFM NiPS3 develops three equivalent AFM domains which are robust against external magnetic field and magnetic coupling with Fe5GeTe2. Consequently, spin frustration at the Fe5GeTe2/NiPS3 interface was shown to develop a perpendicular Fe5GeTe2 magnetization in the interfacial region that switches separately from the bulk of the Fe5GeTe2 magnetizations. In particular, we discover an unconventional spin twisting state that the Fe5GeTe2 spins twist from perpendicular direction near the interface to in-plane direction away from the interface in Fe5GeTe2/NiPS3. Our finding of the twisting spin texture is a unique property of spin frustration in van der Waals magnetic heterostructures.
@article{arxiv.2501.16702,
title = {Spin frustration and unconventional spin twisting state in van der Waals ferromagnet/antiferromagnet heterostructures},
author = {Tianye Wang and Qian Li and Mengmeng Yang and Yu Sun and Alpha T. N'Diaye and Christoph Klewe and Andreas Scholl and Xianzhe Chen and Xiaoxi Huang and Hongrui Zhang and Santai Yang and Xixiang Zhang and Chanyong Hwang and Padraic C. Shafer and Michael F. Crommie and Ramamoorthy Ramesh and Zi Q. Qiu},
journal= {arXiv preprint arXiv:2501.16702},
year = {2025}
}