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arXiv · 2107.11177

Topological aspects of the critical three-state Potts model

Robijn Vanhove·Laurens Lootens·Hong-Hao Tu·Frank Verstraete
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Abstract

We explore the topological defects of the critical three-state Potts spin system on the torus, Klein bottle and cylinder. A complete characterization is obtained by breaking down the Fuchs-Runkel-Schweigert construction of 2d rational CFT to the lattice setting. This is done by applying the strange correlator prescription to the recently obtained tensor network descriptions of string-net ground states in terms of bimodule categories [Lootens, Fuchs, Haegeman, Schweigert, Verstraete, SciPost Phys. 10, 053 (2021)]. The symmetries are represented by matrix product operators (MPO), as well as intertwiners between the diagonal tetracritical Ising model and the non-diagonal three-state Potts model. Our categorical construction lifts the global transfer matrix symmetries and intertwiners, previously obtained by solving Yang-Baxter equations, to MPO symmetries and intertwiners that can be locally deformed, fused and split. This enables the extraction of conformal characters from partition functions and yields a comprehensive picture of all boundary conditions.

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Robijn Vanhove, Laurens Lootens, Hong-Hao Tu, Frank Verstraete. 2021-07-22. Topological aspects of the critical three-state Potts model. https://doi.org/10.1088/1751-8121%2Fac68b1

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