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Resilience of multi-photon entanglement under losses

G. A. Durkin·C. Simon·J. Eisert·D. Bouwmeester
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Abstract

We analyze the resilience under photon loss of the bi-partite entanglement present in multi-photon states produced by parametric down-conversion. The quantification of the entanglement is made possible by a symmetry of the states that persists even under polarization-independent losses. We examine the approach of the states to the set of states with a positive partial transpose as losses increase, and calculate the relative entropy of entanglement. We find that some bi-partite distillable entanglement persists for arbitrarily high losses.

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G. A. Durkin, C. Simon, J. Eisert, D. Bouwmeester. 2004-12-21. Resilience of multi-photon entanglement under losses. https://doi.org/10.1103/physreva.70.062305

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