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arXiv · 2602.09562

Fidelity-Age-Aware Scheduling in Quantum Repeater Networks

Ozgur Ercetin·Zafer Gedik
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Abstract

Quantum repeater networks distribute entanglement over long distances but must balance fidelity, delay, and resource contention. Prior work optimized throughput and end-to-end fidelity, yet little attention has been paid to the freshness of entanglement-the time since a usable Bell pair was last delivered. We introduce the Fidelity-Age (FA) metric, which measures this interval for states whose fidelity exceeds a threshold Fmin. A renewal formulation links slot-level success probability to long-run average FA, enabling a stochastic control problem that minimizes FA under budget and memory limits. Two lightweight schedulers, FA-THR and FA-INDEX, approximate Lyapunov-drift-optimal control. Simulations on slotted repeater grids show that FA-aware scheduling preserves throughput while reducing extreme-age events by up to two orders of magnitude. Fidelity-Age thus provides a tractable, physically grounded metric for reliable and timely entanglement delivery in quantum networks.

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Ozgur Ercetin, Zafer Gedik. 2026-02-10. Fidelity-Age-Aware Scheduling in Quantum Repeater Networks. https://arxiv.org/abs/2602.09562

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