منابع مشابه
Quantum capacity of dephasing channels with memory
We show that the amount of coherent quantum information that can be reliably transmitted down a dephasing channel with memory is maximized by separable input states. In particular, we model the channel as a Markov chain or a multimode environment of oscillators. While in the first model the maximization is achieved for the maximally mixed input state, in the latter it is convenient to exploit t...
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Nicolas J. Cerf, Julien Clavareau, Chiara Macchiavello, and Jérémie Roland QUIC, Ecole Polytechnique, CP 165/59, Université Libre de Bruxelles, B-1050 Brussels, Belgium QUIT, Dipartimento di Fisica “A. Volta,” Universitá di Pavia, via Bassi 6, I-27100 Pavia, Italy Laboratoire de Recherche en Informatique, UMR 8263, Université Paris-Sud, 91405 Orsay, France Received 11 January 2005; published 27...
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Quantum technologies rely on the ability to coherently transfer information encoded in quantum states along quantum channels. Decoherence induced by the environment sets limits on the efficiency of any quantum-enhanced protocol. Generally, the longer a quantum channel is the worse its capacity is. We show that for non-Markovian quantum channels this is not always true: surprisingly the capacity...
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ژورنال
عنوان ژورنال: Physical Review A
سال: 2008
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.78.052114