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Abstract CrSBr is an air‐stable two‐dimensional (2D) van der Waals semiconducting magnet with great technological promise, but its atomic‐scale magnetic interactions—crucial information for high‐frequency switching—are poorly understood. An experimental study is presented to determine the CrSBr magnetic exchange Hamiltonian and bulk magnon spectrum. TheA‐type antiferromagnetic order using single crystal neutron diffraction is confirmed here. The magnon dispersions are also measured using inelastic neutron scattering and rigorously fit the excitation modes to a spin wave model. The magnon spectrum is well described by an intra‐plane ferromagnetic Heisenberg exchange model with seven nearest in‐plane exchanges. This fitted exchange Hamiltonian enables theoretical predictions of CrSBr behavior: as one example, the fitted Hamiltonian is used to predict the presence of chiral magnon edge modes with a spin‐orbit enhanced CrSBr heterostructure.
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Exchange Bias Between van der Waals Materials: Tilted Magnetic States and Field‐Free Spin–Orbit‐Torque Switching
Abstract Magnetic van der Waals heterostructures provide a unique platform to study magnetism and spintronics device concepts in the 2D limit. Here, studies of exchange bias from the van der Waals antiferromagnet CrSBr acting on the van der Waals ferromagnet Fe3GeTe2(FGT) are reported. The orientation of the exchange bias is along the in‐plane easy axis of CrSBr, perpendicular to the out‐of‐plane anisotropy of the FGT, inducing a strongly tilted magnetic configuration in the FGT. Furthermore, the in‐plane exchange bias provides sufficient symmetry breaking to allow deterministic spin–orbit torque switching of the FGT in CrSBr/FGT/Pt samples at zero applied magnetic field. A minimum thickness of the CrSBr of >10 nm is needed to provide a non‐zero exchange bias at 30 K.
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- PAR ID:
- 10485263
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 13
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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