Abstract
We prove that a general upper bound on the maximal mutual information of quantum channels is saturated in the case of Pauli channels with an arbitrary degree of memory. For a subset of such channels we explicitly identify the optimal signal states. We show analytically that for such a class of channels entangled states are indeed optimal above a given memory threshold.
- Received 3 July 2003
DOI:https://doi.org/10.1103/PhysRevA.69.010303
©2004 American Physical Society
