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Optimal entanglement purifying via entanglement swapping

Bao-Sen Shi·Yun-Kun Jiang·Guang-Can Guo
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Abstract

It is known that entanglement swapping can be used to realize entanglement purifying. By this way, two particles belong to different non-maximally entangled pairs can be projected probabilisticly to a maximally entangled state or to a less entangled state. In this report, we show, when the less entangled state is obtained, if a unitary transformation is introduced locally, then a maximally entangled state can be obtained probabilisticly from this less entangled state. The total successful probability of our scheme is equal to the entanglement of a single pairpurification (if two original pairs are in the same non-maximally entangled states) or to the smaller entanglement of a single pair purification of these two pairs (if two original pairs are not in the same non-maximally entangled states). The advantage of our scheme is no continuous indefinite iterative procedure is needed to achieve optimal purifying.

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Bao-Sen Shi, Yun-Kun Jiang, Guang-Can Guo. 2000-05-30. Optimal entanglement purifying via entanglement swapping. https://doi.org/10.1103/physreva.62.054301

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