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arXiv · 2212.03442

Confinement of many-body Bethe strings

Jiahao Yang·Tao Xie·S. E. Nikitin·Jianda Wu·A. Podlesnyak
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Abstract

Based on Bethe-ansatz approach and inelastic neutron scattering experiments, we reveal evolution of confinement of many-body Bethe strings in ordered regions of quasi-one-dimensional antiferromagnet $\rm YbAlO_3$. In the antiferromagnetic phase, the spin dynamics is dominated by the confined length-1 Bethe strings, whose dominancy in the high-energy branch of the excitation spectrum yields to the confined length-2 Bethe strings when the material is tuned to the spin-density-wave phase. In the thermal-induced disordered region, the confinement effect disappears, and the system restores the conventional quantum integrable physics of the one-dimensional Heisenberg model. Our results establish a unified picture based on Bethe string for the spin dynamics in different magnetic phases of $\rm YbAlO_3$, and thus provide profound insight into the many-body quantum magnetism.

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Jiahao Yang, Tao Xie, S. E. Nikitin, Jianda Wu, A. Podlesnyak. 2022-12-07. Confinement of many-body Bethe strings. https://doi.org/10.1103/physrevb.108.l020402

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