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arXiv · 2509.04272

Coherent Two-State Oscillations in False Vacuum Decay Regimes

Peiyun Ge·Xiao Wang·Yu-Xin Chao·Rong Lu·Li You
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Abstract

Coherent two-state oscillations are observed in numerical simulations of the one-dimensional transverse-longitudinal-field Ising model (TLFIM) within false vacuum decay regimes. Starting from the false vacuum (a nearly fully polarized ferromagnetic state), we show that in moderate-sized systems, at resonances $h\approx 2J/n$ (with longitudinal field $h$, transverse field $J$, and an integer $n$), the expected decay can give way to coherent oscillations between the false vacuum and a symmetric resonant state. The oscillation frequency, i.e., the tunneling splitting, is observed notably to exhibit a superradiant-like $\sqrt{L}$ enhancement, as confirmed by a Schrieffer-Wolff analysis. In large chains, coherence remains for $n\gtrsim L/2$ due to bubble-size blockade and is robust against stronger transverse fields; for small $n$, long-range interactions can stabilize the oscillations by lifting multi-bubble degeneracies, establishing a robust many-body coherence mechanism beyond perturbative and finite-size limits.

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Peiyun Ge, Xiao Wang, Yu-Xin Chao, Rong Lu, Li You. 2025-09-04. Coherent Two-State Oscillations in False Vacuum Decay Regimes. https://arxiv.org/abs/2509.04272

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