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arXiv:2307.11511 · Journal of High Energy Physics

The $$ {D}_3^{(2)} $$ spin chain and its finite-size spectrum

Holger Frahm, Sascha Gehrmann, Rafael I. Nepomechie, Ana L. Retore

Published Nov 16, 2023• 1 citation
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Abstract

Abstract Using the analytic Bethe ansatz, we initiate a study of the scaling limit of the quasi-periodic $$ {D}_3^{(2)} $$ D 3 2 spin chain. Supported by a detailed symmetry analysis, we determine the effective scaling dimensions of a large class of states in the parameter regime γ ∈ (0, $$ \frac{\pi }{4} $$ π 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.

DOI
10.1007/jhep11(2023)095

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