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arXiv · 1210.6178

Efficient entanglement concentration for arbitrary less-entangled N-atom state

Lan Zhou
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Abstract

A recent paper (Phys. Rev. A 86, 034305 (2012)) proposed an entanglement concentration protocol (ECP) for less-entangled $N$-atom GHZ state with the help of the photonic Faraday rotation. It is shown that the maximally entangled atom state can be distilled from two pairs of less-entangled atom states. In this paper, we put forward an improved ECP for arbitrary less-entangled N-atom GHZ state with only one pair of less-entangled atom state, one auxiliary atom and one auxiliary photon. Moreover, our ECP can be used repeatedly to obtain a higher success probability. If consider the practical operation and imperfect detection, our protocol is more efficient. This ECP may be useful in current quantum information processing.

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Lan Zhou. 2012-10-23. Efficient entanglement concentration for arbitrary less-entangled N-atom state. https://doi.org/10.1364/josab.30.000071

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