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arXiv · 1908.09568

Broadband pumped polarization entangled photon-pair source in a linear beam displacement interferometer

Alexander Lohrmann·Chithrabhanu Perumangatt·Aitor Villar·Alexander Ling
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Abstract

We experimentally demonstrate a source of polarization entangled photon-pairs based on a single periodically-poled potassium titanyl phosphate (PPKTP) crystal pumped with a broadband, free running laser diode.The crystal is placed within a linear beam-displacement interferometer, and emits photon-pairs based ontype-0 spontaneous parametric downconversion (SPDC). We observe pair rates of 0.56 Mpairs/s/mW in a single spatial mode with a polarization visibility of 97.7% over a spectral range of 100 nm. This experiment demonstrates a pathway towards observing Gigacount rates of polarization entangled photon pairs by using high-power free-running laser diodes with fast multiplexed detectors.

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Alexander Lohrmann, Chithrabhanu Perumangatt, Aitor Villar, Alexander Ling. 2019-11-28. Broadband pumped polarization entangled photon-pair source in a linear beam displacement interferometer. https://doi.org/10.1063/1.5124416

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