Degradability of Bosonic Gaussian channels

Filippo Caruso; Vittorio Giovannetti

doi:10.1103/physreva.74.062307

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Degradability of Bosonic Gaussian channels

Filippo Caruso·Vittorio Giovannetti

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Abstract

The notion of weak-degradability of quantum channels is introduced by generalizing the degradability definition given by Devetak and Shor. Exploiting the unitary equivalence with beam-splitter/amplifier channels we then prove that a large class of one-mode Bosonic Gaussian channels are either weakly degradable or anti-degradable. In the latter case this implies that their quantum capacity Q is null. In the former case instead, this allows us to establish the additivity of the coherent information for those maps which admit unitary representation with single-mode pure environment.

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Filippo Caruso, Vittorio Giovannetti. 2007-02-23. Degradability of Bosonic Gaussian channels. https://doi.org/10.1103/physreva.74.062307

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