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arXiv · 2111.12909

General spin systems without genuinely multipartite nonlocality

Yan-Han Yang·Xue Yang·Ming-Xing Luo
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Abstract

There are multipartite entangled states in many-body systems which may be potential resources in various quantum applications. There are lots of methods to witness specific entangled systems. However, no efficient method is available to explore many-body systems without multipartite entanglement. It may provide necessary restrictions for experimental preparations of multipartite entanglement. Our goal is to solve this problem for spin systems. The maximal effective velocity with propagation of information is bounded in quantum spin systems with short-range interactions from Lieb-Robinson's inequalities. This implies two clustering theorems for ground states and thermal states. With these propagation relations, we show that both the gapped ground state and thermal state at an upper-bounded inverse temperature have no genuine multipartite nonlocality when disjoint regions are far away from each other. The present $n$-particle system shows only biseparable quantum correlations when the propagation relations show exponential decay. Similar result holds for spin systems with product states as initial states. These results show interesting features of quantum many-body systems with exponential decay of correlations.

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Yan-Han Yang, Xue Yang, Ming-Xing Luo. 2021-11-25. General spin systems without genuinely multipartite nonlocality. https://doi.org/10.1140/epjd%2Fs10053-022-00388-5

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