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arXiv · 1009.1609

Bright source of spectrally uncorrelated polarization-entangled photons with nearly single-mode emission

P. G. Evans·J. Schaake·R. S. Bennink·W. P. Grice·T. S. Humble
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Abstract

We present results of a bright polarization-entangled photon source operating at 1552 nm via type-II collinear degenerate spontaneous parametric down-conversion in a periodically poled potassium titanyl phosphate crystal. We report a conservative inferred pair generation rate of 123,000 pairs/s/mW into collection modes. Minimization of spectral and spatial entanglement was achieved by group velocity matching the pump, signal and idler modes and through properly focusing the pump beam. By utilizing a pair of calcite beam displacers, we are able to overlap photons from adjacent down-conversion processes to obtain polarization-entanglement visibility of 94.7 +/- 1.1% with accidentals subtracted.

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P. G. Evans, J. Schaake, R. S. Bennink, W. P. Grice, T. S. Humble. 2010-12-21. Bright source of spectrally uncorrelated polarization-entangled photons with nearly single-mode emission. https://doi.org/10.1103/physrevlett.105.253601

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