2018/07/31 by Federico Grasselli, Hermann Kampermann, Dagmar Bruß
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1088/1367-2630/aaec34
published as 2018 New J. Phys. 20 113014 · 32 pages, 6 figures
arxiv created 2018/11/18 · arxiv updated 2018/12/05
We analyze the security of two multipartite quantum key distribution (QKD) protocols, specifically we introduce an N-partite version of the BB84 protocol and we discuss the N-partite six-state protocol proposed in arXiv:1612.05585v2. The security analysis proceeds from the generalization of known results in bipartite QKD to the multipartite scenario, and takes into account finite resources. In this context we derive a computable expression for the achievable key rate of both protocols by employing the best-known strategies: the uncertainty relation and the postselection technique. We compare the performances of the two protocols both for finite resources and infinitely many signals.