Plug-and-play continuous-variable quantum key distribution for metropolitan networks
We report a plug-and-play continuous variable quantum key distribution system (CV-QKD) with Gaussian modulated quadratures and a true local oscillator. The proposed configuration avoids the need for frequency locking two narrow line-width lasers. To minimize Rayleigh back-scattering, we utilize two independent fiber strands for the distribution of the laser and the transmission of the quantum signals. We further demonstrate the quantum-classical co-existing capability of our system by injecting high-power classical light in both fibers. A secret key rate up to 0.88 Mb/s is obtained by using two fiber links of 13 km and up to 0.3 Mb/s when adding 4 mW of classical light in the optical fiber used for transmitting the quantum signal. The reported performance indicates that the proposed QKD scheme has the potential to become an effective low-cost solution for metropolitan optical networks.
© 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement. Received 28 Feb 2020; revised 17 Apr 2020; accepted 17 Apr 2020; published 28 Apr 2020. We thank Dan Nolan from Corning Inc. for providing the ultralow loss optical fibers used in this work. Funding: Horizon 2020 Framework Programme (820466); Ministerio de Economía y Competitividad (SEV-2015-0522); Fundación Privada Cellex; Fundació Mir-Puig; Generalitat de Catalunya (CERCA program); Vetenskapsrådet (International postdoc grant); Deutscher Akademischer Austauschdienst; European Regional Development Fund (ERDF Operational Program of Catalonia 2014-2020); H2020 Marie Skłodowska-Curie Actions (713729). The authors declare no conflicts of interest.
Published - oe-28-10-14547.pdf