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arXiv · 0705.0047

High photon number path entanglement in the interference of spontaneously downconverted photon pairs with coherent laser light

Holger F. Hofmann·Takafumi Ono
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Abstract

We show that the quantum interference between downconverted photon pairs and photons from coherent laser light can produce a maximally path entangled N-photon output component with a fidelity greater than 90% for arbitrarily high photon numbers. A simple beam splitter operation can thus transform the 2-photon coherence of down-converted light into an almost optimal N-photon coherence.

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Holger F. Hofmann, Takafumi Ono. 2007-08-23. High photon number path entanglement in the interference of spontaneously downconverted photon pairs with coherent laser light. https://doi.org/10.1103/physreva.76.031806

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