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A Practical Scheme for Entanglement Concentration

Zhi Zhao·Jian-Wei Pan·M. S. Zhan
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Abstract

We present a realistic purification scheme for pure non-maximally entangled states. In the scheme, Alice and Bob at two distant parties first start with two shared but less entangled photon pairs to produce a conditional four-photon GHZ state, then perform a 45-degree polarization measurement onto one of the two photons at each party such that the remaining two photons are projected onto a maximally entangled state.

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Zhi Zhao, Jian-Wei Pan, M. S. Zhan. 2001-04-09. A Practical Scheme for Entanglement Concentration. https://doi.org/10.1103/physreva.64.014301

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