We show that entanglement is a useful resource to enhance the mutual information of the depolarizing channel when the noise on consecutive uses of the channel has some partial correlations. We obtain a threshold in the degree of memory, depending on the shrinking factor of the channel, above which a higher amount of classical information is transmitted with entangled signals.
@article{arxiv.quant-ph/0107052,
title = {Entanglement enhanced information transmission over a quantum channel with correlated noise},
author = {Chiara Macchiavello and G. Massimo Palma},
journal= {arXiv preprint arXiv:quant-ph/0107052},
year = {2009}
}