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The capacity of a quantum channel for simultaneous transmission of classical and quantum information

I. Devetak·P. W. Shor
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Abstract

An expression is derived characterizing the set of admissible rate pairs for simultaneous transmission of classical and quantum information over a given quantum channel, generalizing both the classical and quantum capacities of the channel. Although our formula involves regularization, i.e. taking a limit over many copies of the channel, it reduces to a single-letter expression in the case of generalized dephasing channels. Analogous formulae are conjectured for the simultaneous public-private capacity of a quantum channel and for the simultaneously 1-way distillable common randomness and entanglement of a bipartite quantum state.

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I. Devetak, P. W. Shor. 2004-10-21. The capacity of a quantum channel for simultaneous transmission of classical and quantum information. https://arxiv.org/abs/quant-ph/0311131

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