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arXiv · 2310.09490

Anyon condensation web and multipartite entanglement in 2D modulated gauge theories

Abstract

In this work, we introduce an anyon condensation web that interconnects a broad class of 2D fracton gauge theories with multipolar conservation laws at a microscopic level. We find that condensation of anyons triggers the emergence of additional spatially modulated symmetries, which has the general effect of increasing the number of super-selection anyon sectors, as well as the ground state degeneracy for systems with periodic boundary conditions. As explicit examples, we start with the rank-2 toric code model and implement various anyon condensation protocols, resulting in a range of 2D fracton-like theories, each with a distinct gauge structure. We also expand the scope of anyon condensation by introducing lattice defects into spatially modulated gauge theories and demonstrate that these geometric defects can be viewed as effective anyon condensations along the branch cut. Furthermore, we introduce the Multipartite Entanglement Mutual Information measure as a diagnostic tool to differentiate among various distinct multipole conserving phases. A captivating observation is the UV sensitivity of the mutual information sourced from multipartite entanglement in such spatially modulated gauge theories, which depends on the geometric cut and the system size, and exhibits periodic oscillations at large distances.

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Guilherme Delfino, Yizhi You. 2023-10-14. Anyon condensation web and multipartite entanglement in 2D modulated gauge theories. https://doi.org/10.1103/physrevb.109.205146

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