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Physical Review A

Two-photon interference in optical fiber multiports

Gregor Weihs, Michael Reck, Harald Weinfurter, Anton Zeilinger

Published Jul 1, 1996• 49 citations
Publisher

Abstract

We report the measurement of nonclassical photon statistics at the outputs of 2\ifmmode\times\else\texttimes\fi{}2 and 3\ifmmode\times\else\texttimes\fi{}3 fiber couplers resulting from quantum-mechanical second-order interference of entangled photon pairs from a parametric down-conversion source. This is a demonstration of the bunching of bosons at the outputs of fiber multiports. Single-mode fibers provide precise wavelength selection from the down-conversion source spectrum, thus yielding very long coherence times and good collection efficiency without the need of interference filters. Two-photon interference visibilities close to the theoretical maximum were achieved in the experiments. \textcopyright{} 1996 The American Physical Society.

DOI
10.1103/physreva.54.893

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