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arXiv · 2303.06506

Information propagation in long-range quantum many-body systems

Marius Lemm·Carla Rubiliani·Israel Michael Sigal·Jingxuan Zhang
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Abstract

We study general lattice bosons with long-range hopping and long-range interactions decaying as $|x-y|^{-\alpha} $ with $\alpha\in (d+2,2d+1)$. We find a linear light cone for the information propagation starting from suitable initial states. We apply these bounds to estimate the minimal time needed for quantum messaging, for the propagation of quantum correlations, and for quantum state control. The proofs are based on the ASTLO method (adiabatic spacetime localization observables). Our results pose previously unforeseen limitations on the applicability of fast-transfer and entanglement-generation protocols developed for breaking linear light cones in long-range and/or bosonic systems.

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Marius Lemm, Carla Rubiliani, Israel Michael Sigal, Jingxuan Zhang. 2023-03-11. Information propagation in long-range quantum many-body systems. https://arxiv.org/abs/2303.06506

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