Quantum key distribution over 67 km with a plug&play system

Abstract

We present a fibre-optical quantum key distribution system. It works at 1550nm and is based on the plug&play setup. We tested the stability under field conditions using aerial and terrestrial cables and performed a key exchange over 67 km between Geneva and Lausanne.

Experimental plug and play quantum coin flipping

“…Providing security against adversaries of varying complexity is important in the context of current communication networks, where technological and computational capabilities can evolve very rapidly. Furthermore, we experimentally implement the protocol using a practical plug and play system, developed by significantly enhancing a commercial quantum key distribution (QKD) device (http://www.idquantique.com) 31 . The key element of our implementation is that we take a realistic approach: to account for the unavoidable errors in the system and for coherent light source emission statistics, we allow for a non-zero but small probability of abort when both parties are honest, and accept the dependence of the cheating probability on communication loss thus departing from absolute loss tolerance 17,25 .…”

The SECOQC quantum key distribution network in Vienna

“…A scheme of the plug and play auto-compensating system [31,32] designed by id Quantique SA (idQ) is shown in figure 6. It employs a strong laser pulse (λ = 1550 nm) emitted by Bob's laser diode at a frequency of 5 MHz.…”

Quantum counting algorithm and its application in mesoscopic physics

“…While applications in quantum cryptography [1,4] are close to commerical realization [5], the endeavour of building a universal quantum computer with thousands of quantum bits lies in the distant future, if ever realized. In this situation, it is interesting to consider special tasks which are less demanding in their requirement with regard to the number of qubits and the complexity of its network.…”