{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T03:04:06Z","timestamp":1771038246312,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,7]],"date-time":"2023-02-07T00:00:00Z","timestamp":1675728000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["61871407"],"award-info":[{"award-number":["61871407"]}]},{"name":"National Natural Science Foundation of China","award":["61801522"],"award-info":[{"award-number":["61801522"]}]},{"name":"National Natural Science Foundation of China","award":["2022GK2016"],"award-info":[{"award-number":["2022GK2016"]}]},{"name":"Key Research and Development Program of Hunan Province","award":["61871407"],"award-info":[{"award-number":["61871407"]}]},{"name":"Key Research and Development Program of Hunan Province","award":["61801522"],"award-info":[{"award-number":["61801522"]}]},{"name":"Key Research and Development Program of Hunan Province","award":["2022GK2016"],"award-info":[{"award-number":["2022GK2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Continuous variable quantum key distribution (CVQKD) can be potentially implemented through seawater channels, whereas the involved oceanic turbulence has a negative effect on the maximal transmission distance of quantum communication systems. Here, we demonstrate the effects of the oceanic turbulence on the performance of the CVQKD system and suggest an implementation feasibility of the passive CVQKD through the oceanic turbulence-based channel. We achieve the channel transmittance characterized by the transmission distance and depth of the seawater. Moreover, a non-Gaussian approach is used for performance improvement while counteracting the effects of excess noises on the oceanic channel. Numerical simulations show that the photon operation (PO) unit can bring reductions of excess noise when taking into account the oceanic turbulence, and hence results in performance improvement in terms of transmission distance and depth as well. The passive CVQKD explores the intrinsic field fluctuations of a thermal source without using an active scheme and hence has a promising application in chip integration for portable quantum communications.<\/jats:p>","DOI":"10.3390\/e25020307","type":"journal-article","created":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T03:01:45Z","timestamp":1675825305000},"page":"307","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Passive Continuous Variable Quantum Key Distribution through the Oceanic Turbulence"],"prefix":"10.3390","volume":"25","author":[{"given":"Yiwu","family":"Zhu","sequence":"first","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Mao","sequence":"additional","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hui","family":"Hu","sequence":"additional","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yijun","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"057902","DOI":"10.1103\/PhysRevLett.88.057902","article-title":"Continuous Variable Quantum Cryptography Using Coherent States","volume":"88","author":"Grosshans","year":"2002","journal-title":"Phys. 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