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arXiv · 2501.17929

String Breaking in a $2+1$D $\mathbb{Z}_2$ Lattice Gauge Theory

Umberto Borla·Jesse J. Osborne·Sergej Moroz·Jad C. Halimeh
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Abstract

String breaking is an intriguing phenomenon crucial to the understanding of lattice gauge theories (LGTs), with strong relevance to both condensed matter and high-energy physics (HEP). Recent experiments investigating string breaking in $2+1$D (two spatial and one temporal dimensions) LGTs motivate a thorough analysis of its underlying mechanisms. Here, we perform matrix product state (MPS) simulations of string breaking in an experimentally relevant $2+1$D $\mathbb{Z}_2$ LGT in the presence of two external charges. We provide a detailed description of the system in the confined phase, highlight a number of mechanisms which are responsible for string breaking, and argue that magnetic fluctuations have a stabilizing effect on the strings. Moreover, we show that deep in the confined regime the problem is dual to one-dimensional free fermions hopping on an open chain. Our work elucidates the microscopic processes of string breaking in $2+1$D LGTs, and our findings can be probed on current superconducting-qubit quantum computers.

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Umberto Borla, Jesse J. Osborne, Sergej Moroz, Jad C. Halimeh. 2025-01-29. String Breaking in a $2+1$D $\mathbb{Z}_2$ Lattice Gauge Theory. https://arxiv.org/abs/2501.17929

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