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arXiv · 2312.07300

Telecom-Band SPDC in AlGaAs-on-Insulator Waveguides

Marlon Placke·Jan Schlegel·Felix Mann·Pietro Della Casa·Andreas Thies·Markus Weyers·Günther Tränkle·Sven Ramelow
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Abstract

Widespread commercial adoption of telecom-band quantum-key-distribution (QKD) will require fully integrated, room-temperature transmitters. Implementing highly efficient spontaneous parametric down-conversion (SPDC) on a platform that offers co-integration of the pump laser has been an outstanding challenge. Here, using such a platform based on AlGaAs-on-insulator waveguides, we report telecom-band SPDC (and second harmonic generation) with exceedingly large efficiencies of 26 GHz generated pairs/mW over a 7 THz bandwidth, which would saturate the usable photon-flux for a 70-channel wavelength-multiplexed QKD-system at merely 1.6 mW of pump laser power.

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Marlon Placke, Jan Schlegel, Felix Mann, Pietro Della Casa, Andreas Thies, Markus Weyers, Günther Tränkle, Sven Ramelow. 2023-12-12. Telecom-Band SPDC in AlGaAs-on-Insulator Waveguides. https://arxiv.org/abs/2312.07300

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