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Generation of correlated photons in controlled spatial modes by down-conversion in nonlinear waveguides

Konrad Banaszek·Alfred B. U'Ren·Ian A. Walmsley
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Abstract

We report the observation of correlated photon pairs generated by spontaneous parametric down-conversion in a quasi-phase matched KTiOPO4 nonlinear waveguide. The highest ratio of coincidence to single photon count rates observed in the 830 nm wavelength region exceeds 18%. This makes nonlinear waveguides a promising source of correlated photons for metrology and quantum information processing applications. We also discuss possibilities of controlling the spatial characteristics of the down-converted photons produced in multimode waveguide structures.

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Konrad Banaszek, Alfred B. U'Ren, Ian A. Walmsley. 2001-03-07. Generation of correlated photons in controlled spatial modes by down-conversion in nonlinear waveguides. https://doi.org/10.1364/ol.26.001367

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