Sending-or-not-sending twin-field quantum key distribution with discrete-phase-randomized weak coherent states

Jiang，Cong1,2; Yu，Zong Wen2,3; Hu，Xiao Long2; Wang，Xiang Bin1,2,4,5

2020-12-01

10.1103/PhysRevResearch.2.043304

Physical Review Research   影响因子和分区

2643-1564

In many security proofs of quantum key distribution, the random phases of coherent states are assumed to be continuously modulated. However, in practice, we can only take discrete phase randomization to coherent-state sources. In this paper, we study the sending-or-not-sending (SNS) protocol with discrete-phase-randomized coherent states. We present the security proof of the SNS protocol with discrete phase modulation. We then present analytic formulas for key rate calculation. With the decoy-state method and the properties of trace distance, we get the analytical formula of the upper bound of the phase-flip error rate. We also get the lower bound of the yield of untagged bits, which can be calculated by either analytical formula or linear programming. Our numerical simulation results show that with only six phase values, the key rates of the SNS protocol can exceed the linear bound and, with 12 phase values, the key rates are very close to the results of the SNS protocol with continuously modulated phase randomization.

EI

英语

其他

20205109625195

Random processes ; Linear programming ; Quantum theory

Probability Theory:922.1 ; Quantum Theory; Quantum Mechanics:931.4

2-s2.0-85105134219

Scopus

1.Jinan Institute of Quantum Technology,Jinan, Shandong,250101,China
2.State Key Laboratory of Low-Dimensional Quantum Physics,Department of Physics,Tsinghua University,Beijing,100084,China
3.Data Communication Science and Technology Research Institute,Beijing,100191,China
4.Shanghai Branch,Cas Ctr. for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics,University of Science and Technology of China,Shanghai,201315,China
5.Shenzhen Institute for Quantum Science and Engineering and Physics Department,Southern University of Science and Technology,Shenzhen,518055,China

Jiang，Cong,Yu，Zong Wen,Hu，Xiao Long,et al. Sending-or-not-sending twin-field quantum key distribution with discrete-phase-randomized weak coherent states[J]. Physical Review Research,2020,2(4).

Jiang，Cong,Yu，Zong Wen,Hu，Xiao Long,&Wang，Xiang Bin.(2020).Sending-or-not-sending twin-field quantum key distribution with discrete-phase-randomized weak coherent states.Physical Review Research,2(4).

Jiang，Cong,et al."Sending-or-not-sending twin-field quantum key distribution with discrete-phase-randomized weak coherent states".Physical Review Research 2.4(2020).