Dynamics of the Quantum Correlation of Qubits Dissipating into a Common Environment

Xiao-San Ma ； Ying Qiao ； Xiao-Dong Liu ； An-Min Wang

《Chinese Journal of Physics》 52卷1期PartI (2014/02) Pp. 77-89

https://doi.org/10.6122/CJP.52.77

並列摘要

In this paper, we have investigated the dynamics of the quantum correlation between two qubits of a system composed of an arbitrary number of qubits dissipating into a common environment. Our results imply that, when the initial state of the system contains one excitation, the quantum correlation of the quantum discord and the entanglement of formation can be generated between two qubits which have no interaction with each other but are interacting with a common environment. From our analysis, we find that the dynamics of the quantum discord and the entanglement of formation depends not only on the scaled time but also on the size of the system. The larger the size of the system is, the less the quantum discord and the entanglement of formation is generated. By using a comparison between the quantum discord and the entanglement of formation, we find that the quantum discord is more robust to the size of the system than the entanglement of formation is, in the sense that the former decreases more slowly with an increase of the size of the system than the latter does. In addition, the case of the initial state with two excitations is discussed.

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