The security of quantum key distribution(QKD)is severely threatened by discrepancies between realistic devices and theoretical assumptions.Recently,a significant framework called the reference technique was proposed t...The security of quantum key distribution(QKD)is severely threatened by discrepancies between realistic devices and theoretical assumptions.Recently,a significant framework called the reference technique was proposed to provide security against arbitrary source flaws under current technology such as state preparation flaws,side channels caused by mode dependencies,the Trojan horse attacks and pulse correlations.Here,we adopt the reference technique to prove security of an efficient four-phase measurement-device-independent QKD using laser pulses against potential source imperfections.We present a characterization of source flaws and connect them to experiments,together with a finite-key analysis against coherent attacks.In addition,we demonstrate the feasibility of our protocol through a proof-of-principle experimental implementation and achieve a secure key rate of 253 bps with a 20 d B channel loss.Compared with previous QKD protocols with imperfect devices,our study considerably improves both the secure key rate and the transmission distance,and shows application potential in the practical deployment of secure QKD with device imperfections.展开更多
基金supported by the Natural Science Foundation of Jiangsu Province(BK20211145)the Fundamental Research Funds for the Central Universities(020414380182)+1 种基金the Key Research and Development Program of Nanjing Jiangbei New Aera(ZDYD20210101)the Program for Innovative Talents and Entrepreneurs in Jiangsu(JSSCRC2021484)。
文摘The security of quantum key distribution(QKD)is severely threatened by discrepancies between realistic devices and theoretical assumptions.Recently,a significant framework called the reference technique was proposed to provide security against arbitrary source flaws under current technology such as state preparation flaws,side channels caused by mode dependencies,the Trojan horse attacks and pulse correlations.Here,we adopt the reference technique to prove security of an efficient four-phase measurement-device-independent QKD using laser pulses against potential source imperfections.We present a characterization of source flaws and connect them to experiments,together with a finite-key analysis against coherent attacks.In addition,we demonstrate the feasibility of our protocol through a proof-of-principle experimental implementation and achieve a secure key rate of 253 bps with a 20 d B channel loss.Compared with previous QKD protocols with imperfect devices,our study considerably improves both the secure key rate and the transmission distance,and shows application potential in the practical deployment of secure QKD with device imperfections.