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arXiv · 1512.07698

Polarization-entangled photon-pair source obtained via type-II non-collinear SPDC process with PPKTP crystal

Sang Min Lee·Heonoh Kim·Myoungsik Cha·Han Seb Moon
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Abstract

We demonstrate a polarization-entangled photon-pair source obtained via a type-II non-collinear quasi-phase-matched spontaneous parametric down-conversion process with a 10-mm periodically poled KTiOPO$_4$ crystal, which is as stable and wavelength-tunable as the well-known Sagnac configuration scheme. A brightness of 4.2 kHz/mW is detected and a concurrence of 0.975 is estimated using quantum state tomography. Without loss of entanglement and brightness, the photon-pair wavelengths are tunable through control of the crystal temperature. This improvement is achieved using the non-collinear configuration and a stable interferometric distinguishability compensator.

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Sang Min Lee, Heonoh Kim, Myoungsik Cha, Han Seb Moon. 2015-12-24. Polarization-entangled photon-pair source obtained via type-II non-collinear SPDC process with PPKTP crystal. https://doi.org/10.1364/oe.24.002941

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