Passive-state preparation for quantum secure direct communication  

作　　者：Jia-Wei Ying Jin-Yu Wang Yu-Xiang Xiao Shi-Pu Gu Xing-Fu Wang Wei Zhong Ming-Ming Du Xi-Yun Li Shu-Ting Shen An-Lei Zhang Lan Zhou Yu-Bo Sheng 

机构地区：[1]College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing 210023,China [2]Institute of Quantum Information and Technology,Nanjing University of Posts and Telecommunications,Nanjing 210003,China [3]College of Science,Nanjing University of Posts and Telecommunications,Nanjing 210023,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2025年第4期35-44,共10页中国科学:物理学、力学、天文学(英文版)

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.12175106,12405016,and 92365110);the Natural Science Foundation of Jiangsu Province of China(Grant Nos.BK20240611and BK20240612);the Key R&D Program of Guangdong Province(Grant No.2018B030325002)。

摘　　要：Quantum secure direct communication(QSDC)can transmit the secret message directly.Single-photon-based QSDC protocol requires the active modulation of the quantum state of the source,potentially introducing various side-channel vulnerabilities.In this paper,we propose a passive-state preparation QSDC protocol.By utilizing a passive-state preparation method,we remove the need for active modulation,thus eliminating the side-channel risks associated with the source encoder.To evaluate the performance of the protocol,we develop a system model and improve the decoy state method.Through parameter optimization,we identify the optimal secrecy message capacity for various communication distances and compare it with active modulation QSDC.At a communication distance of 10(15)km,the secrecy message capacity of passive-state preparation QSDC reaches3.894×10^(-4)(3.715×10^(-5))bit/pulse,achieving 95.3%(91.5%)of the active case’s performance.Meanwhile,we consider the resource consumption and optimize the secrecy message transmission rate of passive-state preparation QSDC.Using a coherent light source with a frequency of 10^(6)Hz,at communication distances of 5,10,and 15 km,the secrecy message transmission rates for passive-state preparation QSDC reach 2.370×10^(2),4.218×10,and 2.504 bit/s,respectively.

关 键 词：quantum secure direct communication SINGLE-PHOTON passive-state preparation decoy state 

分 类 号：O413[理学—理论物理] TN918[理学—物理]