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arXiv · 2206.06249

High-pressure inelastic neutron scattering study of the anisotropic $S=1$ spin chain [Ni(HF$_2$)(3-Clpyradine)$_4$]BF$_4$

D. M. Pajerowski·A. P. Podlesnyak·J. Herbrych·J. Manson
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Abstract

[Ni(HF$_2$)(3-Clpyradine)$_4$]BF$_4$ (NBCT) is a one-dimensional (1-D), $S=1$ spin chain material that shows no long-range magnetic order down to thermometer temperatures of 0.1 K. Previous ambient pressure inelastic neutron scattering experiments identified NBCT to be in the large-$D$ quantum paramagnetic phase of the $D/J$ phase diagram, where $D$ is the axial single-ion anisotropy and $J$ is the intrachain superexchange. Here, we extend the previous experiments to be at a hydrostatic pressure of 0.9 GPa. By comparing to density matrix renormalization group calculations, we find $D/J$ increases from 1.5 to 3.2 as pressure increases from 0 GPa to 0.9 GPa, which pushes the system further into the large-$D$ phase.

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D. M. Pajerowski, A. P. Podlesnyak, J. Herbrych, J. Manson. 2022-06-13. High-pressure inelastic neutron scattering study of the anisotropic $S=1$ spin chain [Ni(HF$_2$)(3-Clpyradine)$_4$]BF$_4$. https://doi.org/10.1103/physrevb.105.134420

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