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arXiv · 1409.6990

Transverse distinguishability of entangled photons with arbitrarily shaped spatial near- and far-field distributions

Robert Elsner·Dirk Puhlmann·Gregor Pieplow·Axel Heuer·Ralf Menzel
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Abstract

Entangled photons generated by spontaneous parametric down conversion inside a nonlinear crystal exhibit a complex spatial photon count distribution. A quantitative description of this distribution helps with the interpretation of experiments that depend on this structure. We developed a theoretical model and an accompanying numerical calculation that includes the effects of phase matching and the crystal properties to describe a wide range of spatial effects in two-photon experiments. The numerical calculation was tested against selected analytical approximations. We furthermore performed a double-slit experiment where we measured the visibility V and the distinguishability D and obtained $D^2 + V^2 = 1.43$. The numerical model accurately predicts these experimental results.

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Robert Elsner, Dirk Puhlmann, Gregor Pieplow, Axel Heuer, Ralf Menzel. 2014-09-24. Transverse distinguishability of entangled photons with arbitrarily shaped spatial near- and far-field distributions. https://doi.org/10.1364/josab.32.001910

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