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arXiv:1708.06660 · Physical Review A

Regularized maximum pure-state input-output fidelity of a quantum channel

Moritz Ernst, Rochus Klesse

Published Dec 19, 2017• 6 citations
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Abstract

As a toy model for the capacity problem in quantum information theory we investigate finite and asymptotic regularizations of the maximum pure-state input-output fidelity $F(\mathcal{N})$ of a general quantum channel $\mathcal{N}$. We show that the asymptotic regularization $\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{F}(\mathcal{N})$ is lower bounded by the maximum output $\ensuremath{\infty}$-norm ${\ensuremath{\nu}}_{\ensuremath{\infty}}(\mathcal{N})$ of the channel. For $\mathcal{N}$ being a Pauli channel, we find that both quantities are equal.

DOI
10.1103/physreva.96.062319

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