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Production of heralded pure single photons from imperfect sources using cross phase modulation

Thomas Konrad·Michael Nock·Artur Scherer·Juergen Audretsch
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Abstract

Realistic single-photon sources do not generate single photons with certainty. Instead they produce statistical mixtures of photons in Fock states $\ket{1}$ and vacuum (noise). We describe how to eliminate the noise in the output of the sources by means of another noisy source or a coherent state and cross phase modulation (XPM). We present a scheme which announces the production of pure single photons and thus eliminates the vacuum contribution. This is done by verifying a XPM related phase shift with a Mach-Zehnder interferometer.

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Thomas Konrad, Michael Nock, Artur Scherer, Juergen Audretsch. 2006-08-22. Production of heralded pure single photons from imperfect sources using cross phase modulation. https://doi.org/10.1103/physreva.74.032331

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