Walenta, NinoBurg, Andreas PeterCaselunghe, D.Constantin, Jeremy Hugues-FelixGisin, N.Guinnard, O.Houlmann, R.Junod, P.Korzh, B.Kulesza, N.Legré, M.Lim, C. W.Lunghi, T.Monat, L.Portmann, C.Soucarros, M.Thew, R. T.Trinkler, P.Trolliet, G.Vannel, F.Zbinden, H.2014-01-232014-01-232014-01-23201410.1088/1367-2630/16/1/013047https://infoscience.epfl.ch/handle/20.500.14299/100145WOS:000330625700008We present a compactly integrated, 625 MHz clocked coherent one-way quantum key distribution system which continuously distributes secret keys over an optical fibre link. To support high secret key rates, we implemented a fast hardware key distillation engine which allows for key distillation rates up to 4 Mbps in real time. The system employs wavelength multiplexing in order to run over only a single optical fibre. Using fast gated InGaAs single photon detectors, we reliably distribute secret keys with a rate above 21 kbps over 25 km of optical fibre. We optimized the system considering a security analysis that respects finite-key-size effects, authentication costs and system errors for a security parameter of epsilon_QKD = 4 x 10^−9.Quantum CryptographyQuantum Key DistributionQKDSystem DesignSignal ProcessingFPGAtext::journal::journal article::research article