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arXiv · 0709.0847

Experimental position-time entanglement with degenerate single photons

A. J. Bennett·D. G. Gevaux·Z. L. Yuan·A. J. Shields·P. Atkinson·D. A. Ritchie
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Abstract

We report an experiment in which two-photon interference occurs between degenerate single photons that never meet. The two photons travel in opposite directions through our fibre-optic interferometer and interference occurs when the photons reach two different, spatially separated, 2-by-2 couplers at the same time. We show that this experiment is analogous to the conventional Franson-type entanglement experiment where the photons are entangled in position and time. We measure wavefunction overlaps for the two photons as high as 94 $\pm$ 3%.

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A. J. Bennett, D. G. Gevaux, Z. L. Yuan, A. J. Shields, P. Atkinson, D. A. Ritchie. 2008-02-06. Experimental position-time entanglement with degenerate single photons. https://doi.org/10.1103/physreva.77.023803

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