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arXiv · 2605.22947

Entanglement-facilitated macroscopic cluster formation in quantum many-body dynamics

Xiao Wang·Alexander Yosifov·Aditya Iyer·Jinzhao Sun
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Abstract

Metastable quantum many-body dynamics could facilitate the organisation of microscopic degrees of freedom into macroscopic structures. However, the conditions under which this occurs are not well understood. Here we study false-vacuum decay in a 2D quantum Ising model and show that the initial correlation structure can qualitatively change this behaviour. Compared with product-state initialisations, correlated false-vacuum states suppress the proliferation of small true-vacuum domains and favour the formation of macroscopic connected clusters. Tree tensor network simulations of lattices up to $25 \times 25$ further reveal that nucleation proceeds predominantly from the boundary. Finite-size scaling demonstrates the dominant connected cluster remains an extensive fraction of the system even as its size increases. By suppressing this edge-assisted nucleation pathway through boundary pinning, we generate large magnetisation fluctuations consistent with macroscopic superposition. This mechanism relies on the 2D nucleation barrier and is absent in 1D systems or product-state quenches. Our results identify correlated state preparation and boundary engineering as complementary techniques for controlling metastable quantum dynamics.

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Xiao Wang, Alexander Yosifov, Aditya Iyer, Jinzhao Sun. 2026-05-21. Entanglement-facilitated macroscopic cluster formation in quantum many-body dynamics. https://arxiv.org/abs/2605.22947

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