• Abstract Entanglement buffers are systems that maintain high-quality entanglement, ensuring it is readily available for consumption when needed. • We study the performance of a two-node buffer, where each node has one long-lived quantum memory for entanglement storage and multiple short-lived memories for generation. • Freshly generated entanglement may be used to purify stored entanglement, which degrades over time. • Stored entanglement may be removed due to consumption or failed purification. • We derive analytical expressions for the entanglement availability and the average fidelity upon consumption. • Our solutions are computationally efficient and provide fundamental bounds to the performance of purification-based entanglement buffers.
Article Summaries:
- Researchers have derived efficient analytical models for a two‑node entanglement buffer that uses one long‑lived quantum memory per node and several short‑lived memories for generating fresh entanglement. The study quantifies how often freshly generated pairs can purify stored entanglement that degrades over time, and provides closed‑form expressions for entanglement availability and average fidelity at consumption. Results show that maximizing fidelity requires purifying as frequently as possible, even though this can cause loss of high‑quality pairs due to purification failures. The paper also offers practical heuristics for designing purification policies and supplies a GitHub repository with code and a discrete‑event simulator for validation.
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