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arXiv · 1201.2232

Entanglement amplification via local weak measurements

Yukihiro Ota·Sahel Ashhab·Franco Nori
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Abstract

We propose a measurement-based method to produce a maximally-entangled state from a partially-entangled pure state. Our goal can be thought of as entanglement distillation from a single copy of a partially-entangled state. The present approach involves local two-outcome weak measurements. We show that application of these local weak measurements leads to a probabilistic amplification of entanglement. In addition, we examine how the probability to find the maximally-entangled state is related to the entanglement of the input state. We also study the application of our method to a mixed initial state. We show that the protocol is successful if the separable part of the mixed initial state fulfils certain conditions.

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Yukihiro Ota, Sahel Ashhab, Franco Nori. 2012-01-11. Entanglement amplification via local weak measurements. https://doi.org/10.1088/1751-8113/45/41/415303

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