Unambiguous state discrimination in quantum cryptography with weak coherent states
Quantum Physics
2009-10-31 v2
Abstract
The use of linearly independent signal states in realistic implementations of quantum key distribution (QKD) enables an eavesdropper to perform unambiguous state discrimination. We explore quantitatively the limits for secure QKD imposed by this fact taking into account that the receiver can monitor to some extend the photon number statistics of the signals even with todays standard detection schemes. We compare our attack to the beamsplitting attack and show that security against beamsplitting attack does not necessarily imply security against the attack considered here.
Cite
@article{arxiv.quant-ph/9910106,
title = {Unambiguous state discrimination in quantum cryptography with weak coherent states},
author = {Miloslav Dusek and Mika Jahma and Norbert Lütkenhaus},
journal= {arXiv preprint arXiv:quant-ph/9910106},
year = {2009}
}
Comments
10 pages, 6 figures, updated version with added discussion of beamsplitting attack