Parafermionic and decoupled multicritical points in a frustrated $\mathbb{Z}_6$ clock chain

Andrea Kouta Dagnino; Attila Szabó

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arXiv · 2605.03001

Parafermionic and decoupled multicritical points in a frustrated $\mathbb{Z}_6$ clock chain

Andrea Kouta Dagnino·Attila Szabó

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Abstract

We introduce a generalised six-state clock chain that interpolates between the clock and Potts models via a multicritical point described by decoupled Ising and three-state Potts models. We find that this decoupling extends into stable phases that break only $\mathbb{Z}_2$ or $\mathbb{Z}_3$ symmetry. We also use boundary CFT analysis and level spectroscopy to conclusively identify a $\mathbb{Z}_6$ parafermion multicritical point terminating the clock model Luttinger-liquid phase. Our work shows that parafermions emerge far from integrability, even in systems with intertwined Ising and three-state Potts orders.

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Andrea Kouta Dagnino, Attila Szabó. 2026-05-04. Parafermionic and decoupled multicritical points in a frustrated $\mathbb{Z}_6$ clock chain. https://arxiv.org/abs/2605.03001

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