Practical quantum access network over a 10 Gbit/s Ethernet passive\n optical network

Abstract

Quantum key distribution (QKD) provides an information-theoretically secure\nmethod to share keys between legitimate users. To achieve large-scale\ndeployment of QKD, it should be easily scalable and cost-effective. The\ninfrastructure construction of quantum access network (QAN) expands network\ncapacity and the integration between QKD and classical optical communications\nreduces the cost of channel. Here, we present a practical downstream QAN over a\n10 Gbit/s Ethernet passive optical network (10G-EPON), which can support up to\n64 users. In the full coexistence scheme using the single feeder fiber\nstructure, the co-propagation of QAN and 10G-EPON signals with 9 dB attenuation\nis achieved over 21 km fiber, and the secure key rate for each of 16 users\nreaches 1.5 kbps. In the partial coexistence scheme using the dual feeder fiber\nstructure, the combination of QAN and full-power 10G-EPON signals is achieved\nover 11 km with a network capacity of 64-user. The practical QAN over the\n10G-EPON in our work implements an important step towards the achievement of\nlarge-scale QKD infrastructure.\n