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arXiv · 1108.2143

Local-channel-induced rise of quantum correlations in continuous-variable systems

Francesco Ciccarello·Vittorio Giovannetti
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Abstract

It was recently discovered that the quantum correlations of a pair of disentangled qubits, as measured by the quantum discord, can increase solely because of their interaction with a local dissipative bath. Here, we show that a similar phenomenon can occur in continuous-variable bipartite systems. To this aim, we consider a class of two-mode squeezed thermal states and study the behavior of Gaussian quantum discord under various local Markovian non-unitary channels. While these in general cause a monotonic drop of quantum correlations, an initial rise can take place with a thermal-noise channel.

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Francesco Ciccarello, Vittorio Giovannetti. 2012-02-09. Local-channel-induced rise of quantum correlations in continuous-variable systems. https://doi.org/10.1103/physreva.85.022108

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