Advantages of the coherent state compared with squeezed state in unidimensional continuous variable quantum key distribution

  • Xuyang WangEmail author
  • Yanxia Cao
  • Pu Wang
  • Yongmin LiEmail author


In this work, a comparison study between unidimensional (UD) coherent-state and UD squeezed-state protocols is performed in the continuous variable quantum key distribution domain. First, a UD squeezed-state protocol is proposed, and the equivalence between the prepare-and-measure and entanglement-based schemes of UD squeezed-state protocol is proved. Then, the security of the UD squeezed-state protocol under collective attack in realistic conditions is analyzed. Finally, the performance of the two UD protocols is compared. Based on the uniform expressions established in our study, the squeezed- and coherent-state protocols can be analyzed simply by varying the squeezing parameter.


Unidimensional squeezed-state protocol Unidimensional coherent-state protocol Continuous variable quantum key distribution 



This research was supported by the Key Project of the Ministry of Science and Technology of China (2016YFA0301403), National Natural Science Foundation of China (NSFC) (11504219, 61378010), Shanxi 1331KSC, and Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-ElectronicsShanxi UniversityTaiyuanChina
  2. 2.Collaborative Innovation Center of Extreme OpticsShanxi UniversityTaiyuanChina

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