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arXiv · 2510.08533

Fast Mixing of Quantum Spin Chains at All Temperatures

Thiago Bergamaschi·Chi-Fang Chen
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Abstract

It is shown that every one-dimensional Hamiltonian with short-range interaction admits a quantum Gibbs sampler [CKG23] with a system-size independent spectral gap at all finite temperatures. Consequently, their Gibbs states can be prepared in polylogarithmic depth, and satisfy exponential clustering of correlations, generalizing [Ara69].

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Thiago Bergamaschi, Chi-Fang Chen. 2025-10-09. Fast Mixing of Quantum Spin Chains at All Temperatures. https://arxiv.org/abs/2510.08533

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