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arXiv · 2506.19228

Distributing entanglement at the quantum speed limit in Rydberg chains

Kent Ueno·Alexandre Cooper
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Abstract

We numerically study the transport of Rydberg excitations in chains of neutral atoms. We realize an effective flip-flop interaction using off-resonant driving fields. By tuning the relative distances between atoms and applying atom-selective detuning fields, we realize the perfect transport condition. This condition enables the transfer of a single Rydberg excitation from one end of the chain to the other, allowing the distribution of entanglement across the chain at the quantum speed limit. Through numerical simulations, we identify the set of control parameters that maximize the transport probability for experimentally relevant parameters. We study the various competing trade-offs involved in the hierarchy of approximations used to map the native Rydberg spin model onto the effective model driving spin transport. Our results suggest that entanglement can be distributed over chains of more than fifty atoms spanning hundreds of microns at room temperature. This study informs the selection of parameters for the experimental realization of perfect transport in Rydberg chains, providing a new approach to distribute entanglement among distant atoms in quantum processors.

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Kent Ueno, Alexandre Cooper. 2025-06-24. Distributing entanglement at the quantum speed limit in Rydberg chains. https://arxiv.org/abs/2506.19228

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