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arXiv · 2607.17975

Strong Quantum Mpemba Effect from Exact Slow-Mode Selection in Constrained Rydberg Chains

Mingdi Xu·Kaixiang Lu·Zijun Wei·Xiang-Ping Jiang·Haiping Hu·Lei Pan
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Abstract

CStrong quantum Mpemba acceleration requires suppressing the slowest visible Liouvillian relaxation channel, but a robust many-body mechanism for enforcing such suppression remains challenging. We identify such a mechanism in locally dephased constrained Rydberg chains through exact slow-mode selection. For constrained single-spin-flip Hamiltonians, local dephasing turns the Hamiltonian itself into an exact left Liouvillian eigenmode, $\mathcal L^\dagger(H)=-\gamma H$. A finite-temperature reference state generically overlaps with this $H$-like slow mode, whereas translationally invariant states with $\mathrm{Tr}(H\rho_0)=0$ remove it and are confined to the $Q=0$ operator sector. When the next visible $Q=0$ mode decays faster, these selected states exhibit a strong quantum Mpemba effect. We demonstrate this mechanism in the PXP chain for a zero-energy scar eigenstate, the all-zero product state, and a translation-invariant $Z_2$ cat state, and show that it persists in the $(2,3)$ model and the longer-range blockade family. Our results identify Liouvillian mode visibility, rather than special scar wave functions, as the organizing principle for anomalously fast relaxation in constrained open quantum systems.

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Mingdi Xu, Kaixiang Lu, Zijun Wei, Xiang-Ping Jiang, Haiping Hu, Lei Pan. 2026-07-20. Strong Quantum Mpemba Effect from Exact Slow-Mode Selection in Constrained Rydberg Chains. https://arxiv.org/abs/2607.17975

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