{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T20:08:29Z","timestamp":1771618109318,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,3,9]],"date-time":"2022-03-09T00:00:00Z","timestamp":1646784000000},"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>A saturation attack can be employed for compromising the practical security of continuous-variable quantum key distribution (CVQKD). In this paper, we suggest a countermeasure approach to resisting this attack by embedding an adjustable optical filter (AOF) in the CVQKD system. Numerical simulations illustrate the effects of the AOF-enabled countermeasure on the performance in terms of the secret key rate and transmission distance. The legal participants can trace back the information that has been eavesdropped by an attacker from the imperfect receiver, which indicates that this approach can be used for defeating a saturation attack in practical quantum communications.<\/jats:p>","DOI":"10.3390\/e24030383","type":"journal-article","created":{"date-parts":[[2022,3,9]],"date-time":"2022-03-09T11:30:38Z","timestamp":1646825438000},"page":"383","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Counteracting a Saturation Attack in Continuous-Variable Quantum Key Distribution Using an Adjustable Optical Filter Embedded in Homodyne Detector"],"prefix":"10.3390","volume":"24","author":[{"given":"Shengjie","family":"Xu","sequence":"first","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yin","family":"Li","sequence":"additional","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yun","family":"Mao","sequence":"additional","affiliation":[{"name":"School of Automation, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"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"},{"name":"School of Computer, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1301","DOI":"10.1103\/RevModPhys.81.1301","article-title":"The security of practical quantum key distribution","volume":"81","author":"Scarani","year":"2019","journal-title":"Rev. Mod. Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"012325","DOI":"10.1103\/PhysRevA.94.012325","article-title":"Quantum hacking: Saturation attack on practical continuous-variable quantum key distribution","volume":"94","author":"Qin","year":"2016","journal-title":"Phys. Rev. A"},{"key":"ref_3","unstructured":"Bennett, C.H., and Brassard, G. (2020). Quantum cryptography: Public key distribution and coin tossing. arXiv."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"17186","DOI":"10.1364\/OE.27.017186","article-title":"Improvement of self-referenced continuous-variable quantum key distribution with quantum photon catalysis","volume":"27","author":"Ye","year":"2019","journal-title":"Opt. Express"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"14486","DOI":"10.1364\/OE.420583","article-title":"Continuous-variable quantum key distribution coexisting with classical signals on few-mode fiber","volume":"29","author":"Zhong","year":"2021","journal-title":"Opt. Express"},{"key":"ref_6","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. Mod. Phys."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"032604","DOI":"10.1103\/PhysRevA.102.032604","article-title":"Discretely modulated continuous-variable quantum key distribution with an untrusted entanglement source","volume":"102","author":"Liao","year":"2020","journal-title":"Phys. Rev. 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Phys."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"042330","DOI":"10.1103\/PhysRevA.89.042330","article-title":"State-discrimination attack on discretely modulated continuous-variable quantum key distribution","volume":"89","author":"Huang","year":"2014","journal-title":"Phys. Rev. A"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"032327","DOI":"10.1103\/PhysRevA.99.032327","article-title":"Continuous-variable quantum key distribution with non-Gaussian quantum catalysis","volume":"99","author":"Guo","year":"2019","journal-title":"Phys. Rev. A"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"042303","DOI":"10.1103\/PhysRevA.98.042303","article-title":"Long-distance continuous-variable quantum key distribution using separable Gaussian states","volume":"98","author":"Zhou","year":"2018","journal-title":"Phys. Rev. A"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1038\/nature01289","article-title":"Quantum key distribution using gaussian-modulated coherent states","volume":"421","author":"Grosshans","year":"2003","journal-title":"Nature"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"126103","DOI":"10.1016\/j.optcom.2020.126103","article-title":"Nonclassicality and entanglement of single-photon catalysis-assisted two-mode squeezed coherent state","volume":"474","author":"Ye","year":"2020","journal-title":"Opt. Commun."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"19907","DOI":"10.1364\/OE.26.019907","article-title":"Dual-phase-modulated plug-and-play measurement-device-independent continuous-variable quantum key distribution","volume":"26","author":"Liao","year":"2018","journal-title":"Opt. Express"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"012417","DOI":"10.1103\/PhysRevA.103.012417","article-title":"Wavelength attack on atmospheric continuous-variable quantum key distribution","volume":"103","author":"Tan","year":"2021","journal-title":"Phys. Rev. A"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"083073","DOI":"10.1088\/1367-2630\/aba8d4","article-title":"Detecting quantum attacks: A machine learning based defense strategy for practical continuous-variable quantum key distribution","volume":"22","author":"Mao","year":"2020","journal-title":"New J. Phys."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"052323","DOI":"10.1103\/PhysRevA.76.052323","article-title":"Experimental study on the Gaussian-modulated coherent-state quantum key distribution over standard telecommunication fibers","volume":"76","author":"Qi","year":"2007","journal-title":"Phys. Rev. A"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"110501","DOI":"10.1103\/PhysRevLett.107.110501","article-title":"Device calibration impacts security of quantum key distribution","volume":"107","author":"Jain","year":"2011","journal-title":"Phys. Rev. Lett."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"062308","DOI":"10.1103\/PhysRevA.84.062308","article-title":"Attacking a practical quantum-key-distribution system with wavelength-dependent beam-splitter and multiwavelength sources","volume":"84","author":"Li","year":"2011","journal-title":"Phys. Rev. A"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"022320","DOI":"10.1103\/PhysRevA.96.022320","article-title":"Entanglement-distillation attack on continuous-variable quantum key distribution in a turbulent atmospheric channel","volume":"96","author":"Guo","year":"2017","journal-title":"Phys. Rev. A"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"062329","DOI":"10.1103\/PhysRevA.87.062329","article-title":"Quantum hacking of a continuous-variable quantum-key-distribution system using a wavelength attack","volume":"87","author":"Huang","year":"2013","journal-title":"Phys. Rev. A"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"062313","DOI":"10.1103\/PhysRevA.87.062313","article-title":"Preventing calibration attacks on the local oscillator in continuous-variable quantum key distribution","volume":"87","author":"Jouguet","year":"2013","journal-title":"Phys. Rev. A"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"062320","DOI":"10.1103\/PhysRevA.101.062320","article-title":"Hidden-Markov-model-based calibration-attack recognition for continuous-variable quantum key distribution","volume":"101","author":"Mao","year":"2020","journal-title":"Phys. Rev. A"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"032304","DOI":"10.1103\/PhysRevA.89.032304","article-title":"Quantum hacking on quantum key distribution using homodyne detection","volume":"89","author":"Huang","year":"2014","journal-title":"Phys. Rev. A"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"032604","DOI":"10.1103\/PhysRevA.103.032604","article-title":"Passive continuous-variable quantum key distribution using a locally generated local oscillator","volume":"103","author":"Wu","year":"2021","journal-title":"Phys. Rev. A"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"9670","DOI":"10.1364\/OE.422478","article-title":"Saturation compensation for visible light communication with off-the-shelf detectors","volume":"29","author":"Liu","year":"2021","journal-title":"Opt. Express"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"3695","DOI":"10.1364\/OL.40.003695","article-title":"High-speed continuous-variable quantum key distribution without sending a local oscillator","volume":"40","author":"Huang","year":"2015","journal-title":"Opt. 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