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arXiv · 2302.05038

Towards Fully Passive Time-Bin Quantum Key Distribution over Moving Free-Space Channels

Ramy Tannous·Wilson Wu·Stéphane Vinet·Chithrabhanu Perumangatt·Dogan Sinar·Alexander Ling·Thomas Jennewein
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Abstract

Encoding quantum information in photonic time-bin states is typically considered impractical for moving free-space quantum communication due to the difficulties with phase stabilization of distant quantum time-bin interferometers and turbulence of free-space channels. We demonstrate a novel approach using reference frame independent time-bin quantum key distribution that completely avoids the need for active relative phase stabilization while simultaneously overcoming a highly multi-mode channel without any active mode filtering. This scheme enables passive, self-compensating time-bin quantum communication without any mode filtering, mode sorting, adaptive optics, active basis selection, or active phase alignment. We realize a proof-of-concept demonstration using hybrid polarization and time-bin entangled photons that demonstrates a sustained asymptotic secure key rate greater than 0.07 bits/coincidence over a 15m multi-mode fiber optical channel and showing entanglement correlations over a moving 38.5dB loss free-space channel, including system losses. The scheme simplifies the use of time-bin encoding and can be readily applied over various spatially multi-mode and fluctuating channels involving rapidly moving platforms, including airborne and satellite systems.

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Ramy Tannous, Wilson Wu, Stéphane Vinet, Chithrabhanu Perumangatt, Dogan Sinar, Alexander Ling, Thomas Jennewein. 2023-02-10. Towards Fully Passive Time-Bin Quantum Key Distribution over Moving Free-Space Channels. https://doi.org/10.1364/oe.558610

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