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arXiv:0810.4785 · Physical Review A

Photon bunching in parametric down-conversion with continuous-wave excitation

B. Blauensteiner, Isabelle Herbauts, Stefano Bettelli, Andreas Poppe, Hannes Hübel

Published Jun 30, 2009• 60 citations
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Abstract

Direct measurement of photon bunching (${g}_{(2)}$ correlation function) in one output arm of a spontaneous-parametric-down-conversion source operated with a continuous pump laser in the single-photon regime is demonstrated. The result is in agreement with the statistics of a thermal field of the same coherence length and shows the feasibility of investigating photon statistics with compact continuous-wave-pumped sources. Implications for entanglement-based quantum cryptography are discussed.

DOI
10.1103/physreva.79.063846

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Direct measurement of photon bunching (g(2){g}_{(2)}g(2)​ correlation function) in one output arm of a spontaneous-parametric-down-conversion source operated with a continuous pump laser in the single-photon regime is demonstrated. The result is in agreement with the statistics of a thermal field of the same coherence length and shows the feasibility of investigating photon statistics with compact continuous-wave-pumped sources. Implications for entanglement-based quantum cryptography are discussed.
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