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arXiv · 0901.2725

Fully automated entanglement-based quantum cryptography system for telecom fiber networks

Alexander Treiber·Andreas Poppe·Michael Hentschel·Daniele Ferrini·Thomas Lorünser·Edwin Querasser·Thomas Matyus·Hannes Hübel·Anton Zeilinger
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Abstract

We present a quantum key distribution (QKD) system based on polarisation entanglement for use in telecom fibers. A QKD exchange up to 50km was demonstrated in the laboratory with a secure key rate of 550 bit/s. The system is compact, portable with a fully automated start-up and stabilisation modules for polarisation, synchronisation and photon coupling allow a hands-off operation. Stable and reliable key exchange in a deployed optical fiber of 16km length was demonstrated. In this fiber network we achieved over two weeks an automatic key generation with an average key rate of 2000 bit/s without manual intervention. During this period, the system had an average entanglement visibility of 93%, highlighting the technical level and stability achieved for entanglement-based quantum cryptography.

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Alexander Treiber, Andreas Poppe, Michael Hentschel, Daniele Ferrini, Thomas Lorünser, Edwin Querasser, Thomas Matyus, Hannes Hübel, Anton Zeilinger. 2009-04-30. Fully automated entanglement-based quantum cryptography system for telecom fiber networks. https://doi.org/10.1088/1367-2630%2F11%2F4%2F045013

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