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arXiv · 2312.09055

Exploration of magnetoelastic deformations in spin-chain compound CuBr$_2$

Biaoyan Hu·Yingying Peng·Xiaoqiang Liu·Qizhi Li·Qiangqiang Gu·Matthew J. Krogstad·Raymond Osborn·Takashi Honda·Ji Feng·Yuan Li
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Abstract

We investigate a spin-$\frac{1}{2}$ antiferromagnet, CuBr$_2$, which has quasi-one-dimensional structural motifs. The system has previously been observed to exhibit unusual Raman modes possibly due to a locally deformed crystal structure driven by the low-dimensional magnetism. Using hard X-ray scattering and neutron total scattering, here we aim to verify a specific form of tetramerized lattice deformation proposed in the previous study. Apart from diffuse scattering signals which we can reproduce by performing a thorough modeling of the lattice's thermal vibrations, we do not observe evidence for a tetramerized lattice structure within our detection sensitivity. As a result, it is more likely that the unusual Raman modes in CuBr$_2$ arise from classical magnon-phonon hybridization, rather than from quantum spin-singlet-driven lattice deformation.

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Biaoyan Hu, Yingying Peng, Xiaoqiang Liu, Qizhi Li, Qiangqiang Gu, Matthew J. Krogstad, Raymond Osborn, Takashi Honda, Ji Feng, Yuan Li. 2023-12-14. Exploration of magnetoelastic deformations in spin-chain compound CuBr$_2$. https://doi.org/10.1103/physrevb.110.115142

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