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arXiv · 1712.10242

Pilot-assisted intradyne reception for high-speed continuous-variable quantum key distribution with true local oscillator

Fabian Laudenbach·Bernhard Schrenk·Christoph Pacher·Michael Hentschel·Chi-Hang Fred Fung·Fotini Karinou·Andreas Poppe·Momtchil Peev·Hannes Hübel
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Abstract

We present a pilot-assisted coherent intradyne reception methodology for CV-QKD with true local oscillator. An optically phase-locked reference tone, prepared using carrier-suppressed optical single-sideband modulation, is multiplexed in polarisation and frequency to the 250 Mbaud quantum signal in order to provide optical frequency- and phase matching between quantum signal and local oscillator. Our concept allows for high symbol rates and can be operated at an extremely low excess-noise level, as validated by experimental measurements.

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Fabian Laudenbach, Bernhard Schrenk, Christoph Pacher, Michael Hentschel, Chi-Hang Fred Fung, Fotini Karinou, Andreas Poppe, Momtchil Peev, Hannes Hübel. 2019-10-03. Pilot-assisted intradyne reception for high-speed continuous-variable quantum key distribution with true local oscillator. https://doi.org/10.22331/q-2019-10-07-193

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