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arXiv · 0804.2384

Heralded generation of multiphoton entanglement

Philip Walther·Markus Aspelmeyer·Anton Zeilinger
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Abstract

We present a scheme, based only on linear optics and standard photon detection, that allows to generate heralded multiphoton entangled states of arbitrary photon number from spontaneous parametric downconversion (PDC) in the weak interaction regime. The scheme also works in the strong interaction regime, i.e., for the production of large photon numbers, when photon-number resolving detectors with nearly perfect quantum efficiency are used. In addition, the same setup can be used for quantum metrology as multiphoton interferometer with sensitivity at the Heisenberg limit.

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Philip Walther, Markus Aspelmeyer, Anton Zeilinger. 2008-04-15. Heralded generation of multiphoton entanglement. https://doi.org/10.1103/physreva.75.012313

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