Quantum privacy amplification and the security of quantum cryptography over noisy channels
Abstract
Existing quantum cryptographic schemes are not, as they stand, operable in the presence of noise on the quantum communication channel. Although they become operable if they are supplemented by classical privacy-amplification techniques, the resulting schemes are difficult to analyse and have not been proved secure. We introduce the concept of quantum privacy amplification and a cryptographic scheme incorporating it which is provably secure over a noisy channel. The scheme uses an `entanglement purification' procedure which, because it requires only a few quantum Controlled-Not and single-qubit operations, could be implemented using technology that is currently being developed. The scheme allows an arbitrarily small bound to be placed on the information that any eavesdropper may extract from the encrypted message.
Cite
@article{arxiv.quant-ph/9604039,
title = {Quantum privacy amplification and the security of quantum cryptography over noisy channels},
author = {D. Deutsch and A. Ekert and R. Jozsa and C. Macchiavello and S. Popescu and A. Sanpera},
journal= {arXiv preprint arXiv:quant-ph/9604039},
year = {2009}
}
Comments
13 pages, Latex including 2 postcript files included using psfig macros