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Entanglement purification protocols offer a solution by converting multiple low-quality entangled states into a smaller number of higher-quality ones. In this work, we introduce a framework to analyse the performance of entanglement buffering setups that combine entanglement consumption, decoherence, and entanglement purification. We propose two key metrics: the availability, which is the steady-state probability that an entangled link is present, and the average consumed fidelity, which quantifies the steady-state quality of consumed links. We then investigate a two-node system, where each node possesses two quantum memories: one for long-term entanglement storage, and another for entanglement generation. We model this setup as a continuous-time stochastic process and derive analytical expressions for the performance metrics. Our findings unveil a trade-off between the availability and the average consumed fidelity. We also bound these performance metrics for a buffering system that employs the well-known bilocal Clifford purification protocols. Importantly, our analysis demonstrates that, in the presence of noise, consistently purifying the buffered entanglement increases the average consumed fidelity, even when some buffered entanglement is discarded due to purification failures.<\/jats:p>","DOI":"10.22331\/q-2024-09-03-1458","type":"journal-article","created":{"date-parts":[[2024,9,3]],"date-time":"2024-09-03T10:49:34Z","timestamp":1725360574000},"page":"1458","update-policy":"https:\/\/doi.org\/10.22331\/q-crossmark-policy-page","source":"Crossref","is-referenced-by-count":8,"title":["Entanglement buffering with two quantum memories"],"prefix":"10.22331","volume":"8","author":[{"given":"Bethany","family":"Davies","sequence":"first","affiliation":[{"name":"QuTech, Delft Univ. of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands"},{"name":"EEMCS, Quantum Computer Science, Delft Univ. of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands"},{"name":"Kavli Institute of Nanoscience, Delft Univ. of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands"}]},{"given":"\u00c1lvaro G.","family":"I\u00f1esta","sequence":"additional","affiliation":[{"name":"QuTech, Delft Univ. of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands"},{"name":"EEMCS, Quantum Computer Science, Delft Univ. of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands"},{"name":"Kavli Institute of Nanoscience, Delft Univ. of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands"}]},{"given":"Stephanie","family":"Wehner","sequence":"additional","affiliation":[{"name":"QuTech, Delft Univ. of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands"},{"name":"EEMCS, Quantum Computer Science, Delft Univ. of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands"},{"name":"Kavli Institute of Nanoscience, Delft Univ. of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands"}]}],"member":"9598","published-online":{"date-parts":[[2024,9,3]]},"reference":[{"key":"0","doi-asserted-by":"publisher","unstructured":"Sean D. 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