Mask-coding-assisted continuous-variable quantum direct communication with orbital angular momentum multiplexing  

作　　者：Zhengwen Cao Yujie Wang Geng Chai Xinlei Chen Yuan Lu 曹正文;王禹杰;柴庚;陈欣蕾;卢缘

机构地区：[1]Laboratory of Quantum Information&Technology,School of Information Science and Technology,Northwest University,Xi’an 710127,China

出　　处：《Chinese Physics B》2025年第2期64-72,共9页中国物理B(英文版)

基　　金：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);Young Talent Fund of Xi’an Association for Science and Technology (Grant No. 959202313011)。

摘　　要：Quantum secure direct communication(QSDC) is a communication method based on quantum mechanics and it is used to transmit secret messages. Unlike quantum key distribution, secret messages can be transmitted directly on a quantum channel with QSDC. Higher channel capacity and noise suppression capabilities are key to achieving longdistance quantum communication. Here, we report a continuous-variable QSDC scheme based on mask-coding and orbital angular momentum, in which the mask-coding is employed to protect the security of the transmitting messages and to suppress the influence of excess noise. The combination of orbital angular momentum and information block transmission effectively improves the secrecy capacity. In the 800 information blocks ×1310 bits length 10-km experiment, the results show a statistical average bit error rate of 0.38%, a system excess noise value of 0.0184 SNU, and a final secrecy capacity of 6.319×10~6 bps. Therefore, this scheme reduces error bits while increasing secrecy capacity, providing a solution for long-distance large-scale quantum communication, which is capable of transmitting text, images and other information of reasonable size.

关 键 词：continuous-variable quantum direct communication orbital angular momentum mask coding 

分 类 号：O413[理学—理论物理] TN918[理学—物理]