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Title: Spin Waves and Magnetic Exchange Hamiltonian in CrSBr
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.  more » « less
Award ID(s):
1751949
PAR ID:
10571264
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Science
Volume:
9
Issue:
25
ISSN:
2198-3844
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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