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arXiv · 2304.14433

Higher-form Symmetries under Weak Measurement

Kaixiang Su·Nayan Myerson-Jain·Chong Wang·Chao-Ming Jian·Cenke Xu
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Abstract

We aim to address the following question: if we start with a quantum state with a spontaneously broken higher-form symmetry, what is the fate of the system under weak local quantum measurements? We demonstrate that under certain conditions, a phase transition can be driven by weak measurements, which suppresses the spontaneous breaking of the 1-form symmetry and weakens the 1-form symmetry charge fluctuation. We analyze the nature of the transitions employing the tool of duality, and we demonstrate that some of the transitions driven by weak measurement enjoy a line of fixed points with self-duality.

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Kaixiang Su, Nayan Myerson-Jain, Chong Wang, Chao-Ming Jian, Cenke Xu. 2023-04-27. Higher-form Symmetries under Weak Measurement. https://doi.org/10.1103/physrevlett.132.200402

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