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arXiv · 2206.01222

Exactly solvable model for a deconfined quantum critical point in 1D

Carolyn Zhang·Michael Levin
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Abstract

We construct an exactly solvable lattice model for a deconfined quantum critical point (DQCP) in (1+1) dimensions. This DQCP occurs in an unusual setting, namely at the edge of a (2+1) dimensional bosonic symmetry protected topological phase (SPT) with $\mathbb{Z}_2\times\mathbb{Z}_2$ symmetry. The DQCP describes a transition between two gapped edges that break different $\mathbb{Z}_2$ subgroups of the full $\mathbb{Z}_2\times\mathbb{Z}_2$ symmetry. Our construction is based on an exact mapping between the SPT edge theory and a $\mathbb{Z}_4$ spin chain. This mapping reveals that DQCPs in this system are directly related to ordinary $\mathbb{Z}_4$ symmetry breaking critical points.

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Carolyn Zhang, Michael Levin. 2023-02-03. Exactly solvable model for a deconfined quantum critical point in 1D. https://doi.org/10.1103/physrevlett.130.026801

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