J4 ›› 2009, Vol. 26 ›› Issue (4): 437-441.

• Quantum Optics • Previous Articles     Next Articles

Key generation efficiency of practical differential-phase-shift quantum key system with decoy states

ZHAO Feng   

  1. Department of Electronic and Information Engineering, Shaanxi University of Technology, Hanzhong 723003, China
  • Received:2008-08-13 Revised:2008-09-10 Published:2009-07-28 Online:2009-06-29

Abstract:

The security of differential-phase-shift quantum key distribution with weak coherent states is analyzed synthetically. Also, its security which combining decoy states is reevaluated. We have gave out the expressions of key generation efficiency, respectively. The theoretical results indicate that differential-phase-shift quantum key distribution with decoy states is immune from the photon number splitting attacking and the sequential attacking, and its expression of key generation efficiency is identical with Hoi-Kwong et al proposed. The experimental data indicates that the combined system not only achieved longer transmission distance, but also improved the key generation efficiency a factor of ten.

Key words: optical communication, differential phase shift, decoy states, key generation efficiency

CLC Number: