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arXiv · 2411.19034

Noninvertible Symmetry-Enriched Quantum Critical Point

Linhao Li·Rui-Zhen Huang·Weiguang Cao
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Abstract

Noninvertible symmetry generalizes traditional group symmetries, advancing our understanding of quantum matter, especially one-dimensional gapped quantum systems. In critical lattice models, it is usually realized as emergent symmetries in the corresponding low-energy conformal field theories. In this work, we study critical lattice models with the noninvertible Rep($D_8$) symmetry in one dimension. This leads us to a new class of quantum critical points (QCP), noninvertible symmetry-enriched QCPs, as a generalization of known group symmetry-enriched QCPs. They are realized as phase transitions between one noninvertible symmetry-protected topological (SPT) phase and another different one or spontaneous symmetry breaking (SSB) phase. We identify their low-energy properties and topological features through the Kennedy-Tasaki (KT) duality transformation. We argue that distinct noninvertible symmetry-enriched QCPs can not be smoothly connected without a phase transition or a multi-critical point.

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Linhao Li, Rui-Zhen Huang, Weiguang Cao. 2024-11-28. Noninvertible Symmetry-Enriched Quantum Critical Point. https://arxiv.org/abs/2411.19034

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