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Local Conversion of Greenberger-Horne-Zeilinger States to Approximate W States

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 نشر من قبل Philip Walther
 تاريخ النشر 2005
  مجال البحث فيزياء
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Genuine 3-qubit entanglement comes in two different inconvertible types represented by the Greenberger-Horne-Zeilinger (GHZ) state and the W state. We describe a specific method based on local positive operator valued measures and classical communication that can convert the ideal N-qubit GHZ state to a state arbitrarily close to the ideal N-qubit W state. We then experimentally implement this scheme in the 3-qubit case and characterize the input and the final state using 3-photon quantum state tomography.



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