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arXiv · 0806.0115

Nonlocal entanglement concentration scheme for partially entangled multipartite systems with nonlinear optics

Yu-Bo Sheng·Fu-Guo Deng·Hong-Yu Zhou
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Abstract

We present a nonlocal entanglement concentration scheme for reconstructing some maximally entangled multipartite states from partially entangled ones by exploiting cross-Kerr nonlinearities to distinguish the parity of two polarization photons. Compared with the entanglement concentration schemes based on two-particle collective unitary evolution, this scheme does not require the parties to know accurately information about the partially entangled states--i.e., their coefficients. Moreover, it does not require the parties to possess sophisticated single-photon detectors, which makes this protocol feasible with present techniques. By iteration of entanglement concentration processes, this scheme has a higher efficiency and yield than those with linear optical elements. All these advantages make this scheme more efficient and more convenient than others in practical applications.

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Yu-Bo Sheng, Fu-Guo Deng, Hong-Yu Zhou. 2008-06-01. Nonlocal entanglement concentration scheme for partially entangled multipartite systems with nonlinear optics. https://doi.org/10.1103/physreva.77.062325

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