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arXiv · 1202.3019

Efficient two-step entanglement concentration for arbitrary W states

Yu-Bo Sheng·Lan Zhou·Sheng-Mei Zhao
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Abstract

We present two two-step practical entanglement concentration protocols (ECPs) for concentrating an arbitrary three-particle less-entangled W state into a maximally entangled W state assisted with single photons. The first protocol uses the linear optics and the second protocol adopts the cross-Kerr nonlinearity to perform the protocol. In the first protocol, based on the post-selection principle, three parties say Alice, Bob and Charlie in different distant locations can obtain the maximally entangled W state from the arbitrary less-entangled W state with a certain success probability. In the second protocol, it dose not require the parties to posses the sophisticated single-photon detectors and the concentrated photon pair can be retained after performing this protocol successfully. Moreover, the second protocol can be repeated to get a higher success probability. Both protocols may be useful in practical quantum information applications.

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Yu-Bo Sheng, Lan Zhou, Sheng-Mei Zhao. 2012-02-14. Efficient two-step entanglement concentration for arbitrary W states. https://doi.org/10.1103/physreva.85.042302

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