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Finite-key security analysis for multilevel quantum key distribution

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Article number073030
Number of pages15
JournalNew Journal of Physics
Publication statusPublished - 14 Jul 2016
Externally publishedYes
Publication typeA1 Journal article-refereed


Wepresent a detailed security analysis of a d-dimensional quantum key distribution protocol based on two and three mutually unbiased bases (MUBs) both in an asymptotic and finite-key-length scenario. The finite secret key rates (in bits per detected photon) are calculated as a function of the length of the sifted key by (i) generalizing the uncertainly relation-based insight from BB84 to any d-level 2-MUB QKDprotocol and (ii) by adopting recent advances in the second-order asymptotics for finite block length quantum coding (for both d-level 2-and 3-MUBQKDprotocols). Since the finite and asymptotic secret key rates increase with d and the number of MUBs (together with the tolerable threshold) such QKD schemes could in principle offer an important advantage over BB84. We discuss the possibility of an experimental realization of the 3-MUBQKD protocol with the orbital angular momentum degrees of freedom of photons.


  • security of quantum key distribution, finite and asymptotic secret key rates, quantum and private capacity, orbital angular momentum, ORBITAL ANGULAR-MOMENTUM, CRYPTOGRAPHY, ENTANGLEMENT, CANNOT, PROOF