Journal of Naval University of Engineering

Unconditional security boundary of decoy-state quantum key distribution with finite data

Yingjian Wang

Published Jan 1, 2012• 0 citations

Abstract

The decoy-state quantum-key-distribution method(based on a heralded single photon source) is frequently used in experiments serves as an object of study.Using the finite data,it is possible to derive the formula of the lower limit of the single-photon state and the upper limit of the error rate and to obtain the lower limit of key generation rate with unconditional security and the range of secure transmission distance.According to the conclusion drawn from the research,the unconditional security boundary of decoy-state quantum key distribution will be obtained if the number of data-set size is known.The number of transmitted data can also be decided according to the demands for quantum key distribution.In this way,the loop holes in security which are created by finite data can be avoided so as to improve the security and efficiency of quantum key distribution.

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