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arXiv · 1804.11108

High-concurrence time-bin entangled photon pairs from optimized Bragg-reflection waveguides

Huan Chen·Silke Auchter·Maximilian Prilmüller·Alexander Schlager·Thomas Kauten·Kaisa Laiho·Benedikt Pressl·Holger Suchomel·Martin Kamp·Sven Höfling·Christian Schneider·Gregor Weihs
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Abstract

Semiconductor Bragg-reflection waveguides are well-established sources of correlated photon pairs as well as promising candidates for building up integrated quantum optics devices. Here, we use such a source with optimized non-linearity for preparing time-bin entangled photons in the telecommunication wavelength range. By taking advantage of pulsed state preparation and efficient free-running single-photon detection, we drive our source at low pump powers, which results in a strong photon-pair correlation. The tomographic reconstruction of the state's density matrix reveals that our source exhibits a high degree of entanglement. We extract a concurrence of $88.9\pm 1.8\%$ and a fidelity of $94.2 \pm 0.9\%$ with respect to a Bell state.

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Huan Chen, Silke Auchter, Maximilian Prilmüller, Alexander Schlager, Thomas Kauten, Kaisa Laiho, Benedikt Pressl, Holger Suchomel, Martin Kamp, Sven Höfling, Christian Schneider, Gregor Weihs. 2018-04-30. High-concurrence time-bin entangled photon pairs from optimized Bragg-reflection waveguides. https://doi.org/10.1063/1.5038186

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