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arXiv · 1204.5330

A high-brightness source of polarization-entangled photons optimized for applications in free space

Fabian Steinlechner·Pavel Trojek·Marc Jofre·Henning Weier·Daniel Perez·Thomas Jennewein·Rupert Ursin·John Rarity·Morgan W. Mitchell·Juan P. Torres·Harald Weinfurter·Valerio Pruneri
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Abstract

We present a simple but highly efficient source of polarization-entangled photons based on spontaneous parametric down-conversion (SPDC) in bulk periodically poled potassium titanyl phosphate crystals (PPKTP) pumped by a 405 nm laser diode. Utilizing one of the highest available nonlinear coefficients in a non-degenerate, collinear type-0 phase-matching configuration, we generate polarization entanglement via the crossed-crystal scheme and detect 0.64 million photon pair events/s/mW, while maintaining an overlap fidelity with the ideal Bell state of 0.98 at a pump power of 0.025 mW.

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Fabian Steinlechner, Pavel Trojek, Marc Jofre, Henning Weier, Daniel Perez, Thomas Jennewein, Rupert Ursin, John Rarity, Morgan W. Mitchell, Juan P. Torres, Harald Weinfurter, Valerio Pruneri. 2012-04-24. A high-brightness source of polarization-entangled photons optimized for applications in free space. https://doi.org/10.1364/oe.20.009640

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