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arXiv · 2204.12461

Spin waves and magnetic exchange Hamiltonian in CrSBr

A. Scheie·M. Ziebel·D. G. Chica·Y. J. Bae·Xiaoping Wang·A. I. Kolesnikov·Xiaoyang Zhu·X. Roy
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Abstract

CrSBr is an air-stable 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. We present an experimental study to determine the CrSBr magnetic exchange Hamiltonian and bulk magnon spectrum. We confirm the $A$-type antiferromagnetic order using single crystal neutron diffraction. We also measure the magnon dispersions 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, we use the fitted Hamiltonian to predict the presence of chiral magnon edge modes with a spin-orbit enhanced CrSBr heterostructure.

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A. Scheie, M. Ziebel, D. G. Chica, Y. J. Bae, Xiaoping Wang, A. I. Kolesnikov, Xiaoyang Zhu, X. Roy. 2022-04-26. Spin waves and magnetic exchange Hamiltonian in CrSBr. https://doi.org/10.1002/advs.202202467

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