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arXiv · 2101.06173

Inelastic neutron scattering determination of the spin Hamiltonian for BaCdVO(PO$_4$)$_2$

V. K. Bhartiya·S. Hayashida·K. Yu. Povarov·Z. Yan·Y. Qiu·S. Raymond·A. Zheludev
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Abstract

Single crystal inelastic neutron scattering is used to study spin wave excitations in the fully polarized state of the frustrated quantum ferro-antiferromagnet BaCdVO(PO$_4$)$_2$. The data analysis is based on a Heisenberg spin Hamiltonian that includes as many distinct nearest-neighbor and next-nearest neighbor interactions as allowed by crystal symmetry. All 8 such exchange constants are obtained in a simultaneous fit to over 150 scans across the dispersion manifold. This establishes a definitive quantitative model of this material. It turns out to be substantially different from the one assumed in numerous previous studies based on powder experiments.

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V. K. Bhartiya, S. Hayashida, K. Yu. Povarov, Z. Yan, Y. Qiu, S. Raymond, A. Zheludev. 2021-01-15. Inelastic neutron scattering determination of the spin Hamiltonian for BaCdVO(PO$_4$)$_2$. https://doi.org/10.1103/physrevb.103.144402

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