Reliable hands-off entanglement-based QKD system for fiber networks

Quantum cryptography or more specifically quantum key distribution (QKD) is the most advanced quantum information protocol. The field has progressed enormously both in theoretical developments and experimental realisations. We present here an entanglement-based QKD system designed to work at 1550nm for optimal distribution in optical fibers[1] using the BBM92[2] protocol. Our QKD system is realised as a compact device. The start-up and alignment is fully automated and stabilisation routines guarantee a hands-off and long-term operation. We show a reliable and stable key generation during a two-week demonstration over a 16km fiber.