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arXiv · 1208.5705

Invariant Quantum Discord in Qubit-Qutrit Systems under Local Dephasing

G. Karpat·Z. Gedik
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Abstract

We investigate the dynamics of quantum discord and entanglement for a class of mixed qubit-qutrit states assuming that only the qutrit is under the action of a dephasing channel. We demonstrate that even though the entanglement in the qubit-qutrit state disappears in a finite time interval, partial coherence left in the system enables quantum discord to remain invariant throughout the whole time evolution.

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G. Karpat, Z. Gedik. 2012-08-28. Invariant Quantum Discord in Qubit-Qutrit Systems under Local Dephasing. https://doi.org/10.1088/0031-8949%2F2013%2Ft153%2F014036

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