Hannover 2010 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
Q: Fachverband Quantenoptik und Photonik
Q 56: Quantum Information: Quantum Communication II
Q 56.2: Vortrag
Freitag, 12. März 2010, 10:45–11:00, A 310
Quantum key distribution and 1 Gbit/s data encryption over a single fibre — •Nino Walenta1, Patrick Eraerds1, Matthieu Legré2, Nicolas Gisin1, and Hugo Zbinden1 — 1Group of Applied Physics-Optique, University of Geneva, Rue de l'École-de-Médecine 20, 1205 Geneva, Switzerland — 2idQuantique SA, Chemin de la Marbrerie 3, 1227, Geneva, Switzerland
Quantum key distribution (QKD) allows highly secure communication based on the laws of quantum mechanics. Until recently, one of the specifics of QKD systems was the need for a dedicated dark optical fibre, exclusively reserved for the quantum channel. Classical signals, assigned to perform key distillation and encrypted communication between the end users, were sent through separate fibres to not compromise the weak quantum signal.
With the aim for scalable and cost effective deployment we demonstrate QKD in the presence of 4 classical channels in a C-band dense wavelength division multiplexing (DWDM) configuration. The classical channels are used for key distillation and 1 Gbps encrypted communication, rendering the entire system independent from any other communication link than a single dedicated fibre. The separation between quantum channel and nearest classical channel is only 200 GHz, while the classical channels are all separated by 100 GHz. We successfully distil secret keys over fibre spans of up to 50 km. In this context we also discuss DWDM configurations with a quantum channel at 1310 nm.