Degradability of Bosonic Gaussian Channels


Caruso, F. (2007). Degradability of Bosonic Gaussian Channels. Perimeter Institute. https://pirsa.org/07060004


Caruso, Filippo. Degradability of Bosonic Gaussian Channels. Perimeter Institute, Jun. 01, 2007, https://pirsa.org/07060004


          @misc{ pirsa_07060004,
            doi = {},
            url = {https://pirsa.org/07060004},
            author = {Caruso, Filippo},
            keywords = {Quantum Information},
            language = {en},
            title = {Degradability of Bosonic Gaussian Channels},
            publisher = {Perimeter Institute},
            year = {2007},
            month = {jun},
            note = {PIRSA:07060004 see, \url{https://pirsa.org}}


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.