{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,15]],"date-time":"2025-11-15T17:12:44Z","timestamp":1763226764489,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,10,17]],"date-time":"2019-10-17T00:00:00Z","timestamp":1571270400000},"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>Considering the ocean water\u2019s optical attenuation is significantly larger than that of Fiber Channel, we propose an approach to enhance the security of underwater continuous-variable quantum key distribution (CVQKD). In particular, the photon subtraction operation is performed at the emitter to enhance quantum entanglement, thereby improving the underwater transmission performance of the CVQKD. Simulation results show that the photon subtraction operation can effectively improve the performance of CVQKD in terms of underwater transmission distance. We also compare the performance of the proposed protocol in different water qualities, which shows the advantage of our protocol against water deterioration. Therefore, we provide a suitable scheme for establishing secure communication between submarine and submarine vehicles.<\/jats:p>","DOI":"10.3390\/e21101011","type":"journal-article","created":{"date-parts":[[2019,10,17]],"date-time":"2019-10-17T11:07:59Z","timestamp":1571310479000},"page":"1011","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Performance Improvement of Underwater Continuous-Variable Quantum Key Distribution via Photon Subtraction"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1757-7928","authenticated-orcid":false,"given":"Qingquan","family":"Peng","sequence":"first","affiliation":[{"name":"Jiangsu Key Construction Laboratory of IoT Application Technology, School of IoT Engineering, Wuxi Taihu University, Wuxi 214064, China"},{"name":"School of Automation, Central South University, Changsha 410083, China"}]},{"given":"Guojun","family":"Chen","sequence":"additional","affiliation":[{"name":"Jiangsu Key Construction Laboratory of IoT Application Technology, School of IoT Engineering, Wuxi Taihu University, Wuxi 214064, China"}]},{"given":"Xuan","family":"Li","sequence":"additional","affiliation":[{"name":"School of Economics and Management, Jingzhou Institute of Technology, Jingzhou 434020, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7692-7476","authenticated-orcid":false,"given":"Qin","family":"Liao","sequence":"additional","affiliation":[{"name":"College of Computer Science and Electronic Engineering, Hunan University, Changsha 410082, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9306-2061","authenticated-orcid":false,"given":"Ying","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"558","DOI":"10.1119\/1.1463744","article-title":"Quantum computation and quantum information","volume":"70","author":"Nielseen","year":"2003","journal-title":"Am. 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