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arXiv · 1206.2701

Employing long fibre-optical Mach- Zehnder interferometers for quantum cryptography with orthogonal states

G. B. Xavier·G. P. Temporao·J. P. von der Weid
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Abstract

We experimentally demonstrate that a long distance actively stabilized Mach-Zehnder fibre optical interferometer can be used to reliably implement the GV95 quantum cryptography protocol employing orthogonal states. A proof-of-principle experiment using an interferometer composed of 1 km of spooled optical fibres connecting Alice and Bob is performed. The active stabilisation against phase drifts is done with a classical channel wavelength-multiplexed with the quantum channel and a high stable visibility implying a QBER of 2.2 % is shown.

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G. B. Xavier, G. P. Temporao, J. P. von der Weid. 2012-06-13. Employing long fibre-optical Mach- Zehnder interferometers for quantum cryptography with orthogonal states. https://arxiv.org/abs/1206.2701

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