Abstract Continuous-variable quantum secure direct communication (CVQSDC) with Gaussian modulation (GM) demands a considerable quantity of random numbers during the preparation process and encodes them separately on the quadrature components of the quantum states. Hence, high-speed random number generators are required to satisfy this demand, which is difficult to implement in practical applications. CVQSDC with discrete modulation (DM), correspondingly, employs a finite number of quantum states to achieve encoding, which can circumvent the shortcomings of the GM scheme. Based on the advantages of DM, the issue of attaining the most optimal secrecy capacity and communication distance remains to be resolved. Here, we propose a CVQSDC protocol based on -symbol amplitude phase shift keying (-APSK), which exploits the Boltzmann-Maxwell distribution assisted probability shaping technique. In comparison with the uniform distribution, according to 32-APSK CVQSDC, the proposed scheme extends the communication distance by about 38%, while obtaining a higher secrecy capacity at the same communication distance. Furthermore, increasing the value of will concurrently increase the quantity of rings in the constellation, thereby facilitating enhancements of communication distance. This work incorporates the modulation approaches prevalently employed in classical communication into the realm of quantum communication, attaining gratifying advancements in communication distance and secrecy capacity, and concurrently facilitating the integrated development of quantum communication and classical communication.
(Optical implementations of quantum information processing and transfer)
Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 62071381 and 62301430), Shaanxi Fundamental Science Research Project for Mathematics and Physics (Grant No. 23JSY014), Scientific Research Plan Project of Shaanxi Education Department (Natural Science Special Project (Grant No. 23JK0680), and Young Talent Fund of Xi’an Association for Science and Technology (Grant No. 959202313011).
Zheng-Wen Cao(曹正文), Yu-Jie Zhang(张昱洁), Geng Chai(柴庚), Zhang-Tao Liang(梁章韬), Xin-Lei Chen(陈欣蕾), Lei Wang(王磊), and Yu-Jie Wang(王禹杰) Continuous-variable quantum secure direct communication based on N-APSK with Boltzmann-Maxwell distribution 2025 Chin. Phys. B 34 030303
[1] Pirandola S, Andersen U L, Banchi L, et al. 2020 Adv. Opt. Photonics 12 1012 [2] Long G L and Liu X S 2002 Phys. Rev. A 65 032302 [3] Boström K and Felbinger T 2002 Phys. Rev. Lett. 89 187902 [4] Deng F G, Long G L and Liu X S 2003 Phys. Rev. A 68 042317 [5] Deng F G and Long G L 2004 Phys. Rev. A 69 052319 [6] Wang C, Deng F G, Li Y S, Liu X S and Long G L 2005 Phys. Rev. A 71 044305 [7] Jin X R, Ji X, Zhang Y Q, Zhang S, Hong S K, Yeon K H and Um C I 2006 Phys. Lett. A 354 67 [8] Cao Z W, Wang L, Liang K X, Chai G and Peng J Y 2021 Phys. Rev. Appl. 16 024012 [9] Sheng Y B, Zhou L and Long G L 2022 Sci. Bull. 67 367 [10] Cao Z W, Lu Y, Chai G, Yu H, Liang K X and Wang L 2023 Research 6 0193 [11] Liang K X, Cao Z W, Chen X L, Wang L, Chai G and Peng J Y 2023 Front. Phys. 18 51301 [12] Zhao P, ZhongW, DuMM, Li X Y, Zhou L and Sheng Y B 2024 Front. Phys. 19 51201 [13] Zhang Q, Du M M, Zhong W, Sheng Y B and Zhou L 2024 Ann. Phys. 536 2300407 [14] Wang L, Chai G, Cao ZW, Chen X L, Liang K X G and Peng J Y 2025 Sci. China Phys. Mech. Astron. 68 220313 [15] Niu P H, Zhou Z R,Lin Z S, Sheng Y B, Yin L G and Long G L 2018 Sci. Bull. 63 1345 [16] Wu X D, Zhou L, Zhong W and Sheng Y B 2020 Sci. Bull. 19 354 [17] Zhou L, Sheng Y B and Long G L 2020 Sci. Bull. 65 12 [18] Zhou Z R, Sheng Y B, Niu P H, Yin L G, Long G L and Hanzo L 2020 Sci. China Phys. Mech. Astron. 63 230362 [19] Ying J W, Zhou L, Zhong W and Sheng Y B 2022 Chin. Phys. B 31 120303 [20] Zhou L, Xu B W, Zhong W and Sheng Y B 2023 Phys. Rev. Appl. 19 014036 [21] Zeng H, Du M M, Zhong W, Zhou L and Sheng Y B 2024 Fundam. Res. 4 851 [22] Grosshans F and Grangier P 2002 Phys. Rev. Lett. 88 057902 [23] Grosshans F, Van Assche G,Wenger J, Brouri R, Cerf N J and Grangier Ph 2003 Nature 421 238 [24] Hirano T, Ichikawa T, Matsubara T, Ono M, Oguri Y, Namiki R, Kasai K, Matsumoto R and Tsurumaru T 2017 Quantum Sci. Technol. 2 024010 [25] Ghorai S,Grangier P, Diamanti E and Leverrier A 2019 Phys. Rev. X 9 021059 [26] Leverrier A and Grangier P 2009 Phys. Rev. Lett. 102 180504 [27] Zhao W, Shi R H, Feng Y T and Huang D 2020 Phys. Lett. A 384 126061 [28] Wang P, Zhang Y, Lu Z G, Wang X Y and Li Y M 2023 New J. Phys. 25 023019 [29] Sych D and Leuchs G 2010 New J. Phys. 12 053019 [30] Becir A, El-Orany F A A and Wahiddin M R B 2012 Int. J. Quantum Inf. 10 1250004 [31] Almeida M, Pereira D, Muga N J, Facão M, Pinto A N and Silva N A 2021 Opt. Express 29 38669 [32] Almeida M, Pereira D, Facão M, Pinto A N and Silva N A 2023 J. Lightwave Technol. 41 6134 [33] Gong L H, Song H C, He C S, Liu Y and Zhou N R 2014 Phys. Scr. 89 035101 [34] Duan L M, Giedke G, Cirac J I and Zoller P 2000 Phys. Rev. Lett. 84 2722 [35] Gaudenzi D R, Fabregas I G A and Martinez A 2006 IEEE Trans. Wireless Commun. 5 2396 [36] Deng F G, Long G L and Liu X S 2003 Phys. Rev. A 68 042317 [37] Lodewyck J, Bloch M, García-Patrón R, Fossier S, Karpov E, Diamanti E, Debuisschert T, Cerf NJ, Tualle-Brouri R, McLaughlin S W and Grangier P 2007 Phys. Rev. A 76 042305 [38] Wu J, Lin Z, Yin L and Long G L 2019 Quantum Engineering 1 e26 [39] Denys A, Brown P and Leverrier A 2021 Quantum 5 540
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