Journal of Physics A Mathematical and General

Decoherence of continuous variable quantum information in non-Markovian channels

Masashi Ban

Published Feb 8, 2006• 56 citations

Abstract

Decoherence of quantum information carried by single-mode and two-mode Gaussian states is investigated under the influence of non-Markovian quantum channels, where correlation times of reservoir variables are assumed to take finite values. Degradation of purity, distinguishability and non-classicality of single-mode Gaussian states and relaxation of entanglement of two-mode Gaussian states are examined. The results show the importance of the non-Markovian effect of a thermal reservoir. Furthermore, continuous variable quantum teleportation is considered when a sender and a receiver share a two-mode Gaussian state through non-Markovian quantum channels.

DOI: 10.1088/0305-4470/39/8/010

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