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arXiv · 2011.03843

Increasing the link-distance of free-space quantum coherent communication with large area detectors

Rupesh Kumar·Igor Konieczniak·Gerald Bonner·Tim Spiller
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Abstract

We report a large area photo-diode based homodyne detector for free-space quantum coherent communication. The detector's performance is studied in terms of detection bandwidth and electronic noise for shot-noise limited quantum signal detection. Using large area photo-diodes increases signal collection efficiency from turbulent atmospheric channels, in comparison with typical fibre based free-space homodyne detectors. Under identical atmospheric turbulence and receiver aperture conditions, our homodyne detector based on 1mm diameter photo-diode experiences 0dB loss due to turbulence while a 10um fibre based detector experiences 13.5dB of signal loss over a 700km free-space link, at 90 degree elevation angle.

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Rupesh Kumar, Igor Konieczniak, Gerald Bonner, Tim Spiller. 2020-11-07. Increasing the link-distance of free-space quantum coherent communication with large area detectors. https://arxiv.org/abs/2011.03843

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