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arXiv · 2307.11511

The $D^{(2)}_{3}$ spin chain and its finite-size spectrum

Holger Frahm·Sascha Gehrmann·Rafael I. Nepomechie·Ana L. Retore
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Abstract

Using the analytic Bethe ansatz, we initiate a study of the scaling limit of the quasi-periodic $D^{(2)}_3$ spin chain. Supported by a detailed symmetry analysis, we determine the effective scaling dimensions of a large class of states in the parameter regime $\gamma\in (0,\frac{\pi}{4})$. Besides two compact degrees of freedom, we identify two independent continuous components in the finite-size spectrum. The influence of large twist angles on the latter reveals also the presence of discrete states. This allows for a conjecture on the central charge of the conformal field theory describing the scaling limit of the lattice model.

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Holger Frahm, Sascha Gehrmann, Rafael I. Nepomechie, Ana L. Retore. 2023-07-21. The $D^{(2)}_{3}$ spin chain and its finite-size spectrum. https://doi.org/10.1007/jhep11(2023)095

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