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arXiv · 2403.19778

Imperfect quantum networks with tailored resource states

Maria Flors Mor-Ruiz·Julius Wallnöfer·Wolfgang Dür
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Abstract

Entanglement-based quantum networks exhibit a unique flexibility in the choice of entangled resource states that are then locally manipulated by the nodes to fulfill any request in the network. Furthermore, this manipulation is not uniquely defined and thus can be optimized. We tailor the adaptation of the resource state or pre-established entanglement to achieve bipartite communication in an imperfect setting that includes time-dependent memory errors. In this same setting, we study how the flexibility of this approach can be used for the distribution of entanglement in a fully asymmetric network scenario. The considered entanglement topology is a custom one based on the minimization of the required measurements to retrieve a Bell pair. The optimization of the manipulation and the study of such a custom entanglement topology are performed using the noisy stabilizer formalism, a recently introduced method to fully track noise on graph states. We find that exploiting the flexibility of the entanglement topology, given a certain set of bipartite requests, is highly favorable in terms of the fidelity of the final state.

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Maria Flors Mor-Ruiz, Julius Wallnöfer, Wolfgang Dür. 2024-03-28. Imperfect quantum networks with tailored resource states. https://doi.org/10.22331/q-2025-01-21-1605

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