Multi-party Agile Quantum Key Distribution Network with a Broadband Fiber-based Entangled Source
E. Y. Zhu, Costantino Corbari, Alexey V. Gladyshev, Peter G. Kazansky, Hoi‐Kwong Lo, Li Qian · arXiv (Cornell University) · 2015
A reconfigurable, multi-party quantum key distribution sch eme is experimentally demonstrated by utilizing a poled fiber-b ased source of broadband polarization-entangled photon pairs and dense wavelength- division multiplexing (DWDM). The large bandwidth (> 90 nm centered about 1555 nm) and highly spectrally-correlated nature of the entangled source is exploited to allow for the generation of more than 25 frequency- conjugate entangled pairs when aligned to the standard 200-GHz ITU grid. Such a network can serve more than 50 users simultaneously, allowing any one user on the network to establish a QKD link with any other user through wavelength-selective switching. The entangled pairs are delivered over 40 km of actual fiber (equivalent to 120 km of fiber based on channe l-loss experienced), and a secure key rate of more than 20 bits/s per bi-party is observed.