{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T14:51:24Z","timestamp":1778770284041,"version":"3.51.4"},"reference-count":55,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2015,6,26]],"date-time":"2015-06-26T00:00:00Z","timestamp":1435276800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>We propose a method to improve the performance of two entanglement-based continuous-variable quantum key distribution protocols using noiseless linear amplifiers. The two entanglement-based schemes consist of an entanglement distribution protocol with an untrusted source and an entanglement swapping protocol with an untrusted relay. Simulation results show that the noiseless linear amplifiers can improve the performance of these two protocols, in terms of maximal transmission distances, when we consider small amounts of entanglement, as typical in realistic setups.<\/jats:p>","DOI":"10.3390\/e17074547","type":"journal-article","created":{"date-parts":[[2015,6,26]],"date-time":"2015-06-26T10:24:46Z","timestamp":1435314286000},"page":"4547-4562","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Noiseless Linear Amplifiers in Entanglement-Based Continuous-Variable Quantum Key Distribution"],"prefix":"10.3390","volume":"17","author":[{"given":"Yichen","family":"Zhang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhengyu","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Electronics Engineering and Computer Science, Center for Quantum Information Technology and Center for Computational Science and Engineering, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christian","family":"Weedbrook","sequence":"additional","affiliation":[{"name":"QKD Corp., 60 St. George St., Toronto, M5S 1A7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kevin","family":"Marshall","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Toronto, Toronto, M5S 1A7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefano","family":"Pirandola","sequence":"additional","affiliation":[{"name":"Department of Computer Science, University of York, Deramore Lane, York YO10 5GH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Song","family":"Yu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hong","family":"Guo","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"},{"name":"State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Electronics Engineering and Computer Science, Center for Quantum Information Technology and Center for Computational Science and Engineering, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,6,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1103\/RevModPhys.74.145","article-title":"Quantum cryptography","volume":"74","author":"Gisin","year":"2002","journal-title":"Rev. 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