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arXiv · 2403.09287

Duality and hidden symmetry breaking in the q-deformed Affleck-Kennedy-Lieb-Tasaki model

Tyler Franke·Thomas Quella
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Abstract

We revisit the question of string order and hidden symmetry breaking in the q-deformed AKLT model, an example of a spin chain that possesses generalized symmetry. We first argue that the non-local Kennedy-Tasaki duality transformation that was previously proposed to relate the string order to a local order parameter leads to a non-local Hamiltonian and thus does not provide a physically adequate description of the symmetry breaking. We then present a modified non-local transformation which is based on a recently developed generalization of Witten's Conjugation to frustration-free lattice models and capable of resolving this issue.

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Tyler Franke, Thomas Quella. 2024-03-14. Duality and hidden symmetry breaking in the q-deformed Affleck-Kennedy-Lieb-Tasaki model. https://doi.org/10.21468/scipostphyscore.7.4.078

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