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arXiv · 2010.03968

Quantum Correlation Dynamics in Controlled Two-Coupled-Qubit Systems

Iulia Ghiu·Roberto Grimaudo·Tatiana Mihaescu·Aurelian Isar·Antonino Messina
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Abstract

We study and compare the time evolutions of concurrence and quantum discord in a driven system of two interacting qubits prepared in a generic Werner state. The~corresponding quantum dynamics is exactly treated and manifests the appearance and disappearance of entanglement. Our analytical treatment transparently unveils the physical reasons for the occurrence of such a phenomenon, relating it to the dynamical invariance of the $X$ structure of the initial state. The~quantum correlations which asymptotically emerge in the system are investigated in detail in terms of the time evolution of the fidelity of the initial Werner state.

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Iulia Ghiu, Roberto Grimaudo, Tatiana Mihaescu, Aurelian Isar, Antonino Messina. 2020-10-08. Quantum Correlation Dynamics in Controlled Two-Coupled-Qubit Systems. https://doi.org/10.3390/e22070785

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