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arXiv · 1705.04355

Lieb-Robinson bounds on $n$-partite connected correlation functions

Minh Cong Tran·James R. Garrison·Zhe-Xuan Gong·Alexey V. Gorshkov
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Abstract

Lieb and Robinson provided bounds on how fast bipartite connected correlations can arise in systems with only short-range interactions. We generalize Lieb-Robinson bounds on bipartite connected correlators to multipartite connected correlators. The bounds imply that an $n$-partite connected correlator can reach unit value in constant time. Remarkably, the bounds also allow for an $n$-partite connected correlator to reach a value that is exponentially large with system size in constant time, a feature which stands in contrast to bipartite connected correlations. We provide explicit examples of such systems.

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Minh Cong Tran, James R. Garrison, Zhe-Xuan Gong, Alexey V. Gorshkov. 2017-05-11. Lieb-Robinson bounds on $n$-partite connected correlation functions. https://doi.org/10.1103/physreva.96.052334

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