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arXiv · 1611.06048

Symmetry in the open-system dynamics of quantum correlations

Henri Lyyra·Göktuğ Karpat·Chuan-Feng Li·Guang-Can Guo·Jyrki Piilo·Sabrina Maniscalco
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Abstract

We study the symmetry properties in the dynamics of quantum correlations for two-qubit systems in one-sided noisy channels, with respect to a switch in the location of noise from one qubit to the other. We consider four different channel types, namely depolarizing, amplitude damping, bit-flip, and bit-phase-flip channel, and identify the classes of initial states leading to symmetric decay of entanglement, non-locality and discord. Our results show that the symmetric decay of quantum correlations is not directly linked to the presence or absence of symmetry in the initial state, while it does depend on the type of correlation considered as well as on the type noise. We prove that asymmetric decay can be used to infer, in certain cases, characteristic properties of the channel. We also show that the location of noise may lead to dramatic changes in the persistence of phenomena such as entanglement sudden death and time-invariant discord.

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Henri Lyyra, Göktuğ Karpat, Chuan-Feng Li, Guang-Can Guo, Jyrki Piilo, Sabrina Maniscalco. 2016-11-18. Symmetry in the open-system dynamics of quantum correlations. https://doi.org/10.1038/s41598-017-08457-1

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