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arXiv · 1303.2852

Universal and optimal error thresholds for measurement-based entanglement purification

M. Zwerger·H. J. Briegel·W. Dür
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Abstract

We investigate measurement-based entanglement purification protocols (EPP) in the presence of local noise and imperfections. We derive a universal, protocol-independent threshold for the required quality of the local resource states, where we show that local noise per particle of up to 24% is tolerable. This corresponds to an increase of the noise threshold by almost an order of magnitude, based on the joint measurement-based implementation of sequential rounds of few-particle EPP. We generalize our results to multipartite EPP, where we encounter similarly high error thresholds.

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M. Zwerger, H. J. Briegel, W. Dür. 2013-03-12. Universal and optimal error thresholds for measurement-based entanglement purification. https://doi.org/10.1103/physrevlett.110.260503

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