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arXiv · 0812.4612

Tri-partite Entanglement Witnesses and Sudden Death

Yaakov S. Weinstein
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Abstract

I explore entanglement dynamics in a three qubit system comparing the ability of entanglement witnesses to detect tri-partite entanglement to the phenomenon of entanglement sudden death (ESD). Using a system subject to dephasing I invoke entanglement witnesses to detect tri-partite GHZ and W-type entanglement and compare the evolution of their detection capabilites with the evolution of the negativity, bi-partite concurrence, and tri-partite negativity. Interestingly, I find a state in which there is no concurrence or tri-partite negativity but there is entanglement. Finally, I utilize a three qubit quantum error correction (QEC) code to address how ESD affects the abilities of quantum error correction.

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Yaakov S. Weinstein. 2008-12-25. Tri-partite Entanglement Witnesses and Sudden Death. https://doi.org/10.1103/physreva.79.012318

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