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arXiv · 0902.2697

Entanglement Sudden Death as an Indicator of Fidelity in a Four-Qubit Cluster State

Yaakov S. Weinstein
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Abstract

I explore the entanglement evolution of a four qubit cluster state in a dephasing environment concentrating on the phenomenon of entanglement sudden death (ESD). Specifically, I ask whether the onset of ESD has an effect on the utilization of this cluster state as a means of implementing a single qubit rotation in the measurement based cluster state model of quantum computation. To do this I compare the evolution of the entanglement to the fidelity, a measure of how accurately the desired state (after the measurement based operations) is achieved. I find that ESD does not cause a change of behavior or discontinuity in the fidelity but may indicate when the fidelity of certain states goes to .5.

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Yaakov S. Weinstein. 2009-02-16. Entanglement Sudden Death as an Indicator of Fidelity in a Four-Qubit Cluster State. https://doi.org/10.1103/physreva.79.052325

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