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arXiv · 0810.0550

Nonexistence of Entanglement Sudden Death in High NOON States

Asma Al-Qasimi·Daniel F. V. James
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Abstract

We study the dynamics of entanglement in continuous variable quantum systems (CVQS). Specifically, we study the phenomena of Entanglement Sudden Death (ESD) in general two-mode-N-photon states undergoing pure dephasing. We show that for these states, ESD never occurs. These states are generalizations of the so-called High NOON states, shown to decrease the Rayleigh limit of lambda to lambda/N, which promises great improvement in resolution of interference patterns if states with large N are physically realized. However, we show that in dephasing NOON states, the time to reach V_crit, critical visibility, scales inversely with N^2. On the practical level, this shows that as N increases, the visibility degrades much faster, which is likely to be a considerable drawback for any practical application of these states.

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Asma Al-Qasimi, Daniel F. V. James. 2008-10-02. Nonexistence of Entanglement Sudden Death in High NOON States. https://doi.org/10.1364/ol.34.000268

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