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arXiv · 2503.20859

BaCo$_2$(AsO$_4$)$_2$: Strong Kitaev, After All

Pavel A. Maksimov·Shengtao Jiang·L. P. Regnault·A. L. Chernyshev
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Abstract

The inelastic neutron scattering results and their analysis unequivocally point to a dominant Kitaev interaction in the honeycomb-lattice cobaltate BaCo$_2$(AsO$_4$)$_2$. Our anisotropic-exchange model closely describes $all$ available neutron scattering data in the material's field-polarized phase. The density-matrix renormalization group results for our model are in close accord with the unusual double-zigzag magnetic order and the low in-plane saturation field of BaCo$_2$(AsO$_4$)$_2$.

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Pavel A. Maksimov, Shengtao Jiang, L. P. Regnault, A. L. Chernyshev. 2025-03-26. BaCo$_2$(AsO$_4$)$_2$: Strong Kitaev, After All. https://doi.org/10.1103/k1gq-k8m7

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