Continuous variable quantum key distribution using polarization encoding and post selection

Stefan Lorenz; Natalia Korolkova; Gerd Leuchs

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arXiv · quant-ph/0403064

Continuous variable quantum key distribution using polarization encoding and post selection

Stefan Lorenz·Natalia Korolkova·Gerd Leuchs

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Abstract

We present an experimental demonstration of a quantum key distribution protocol using coherent polarization states. Post selection is used to ensure a low error rate and security against beam splitting attacks even in the presence of high losses. Signal encoding and readout in polarization bases avoids the difficult task of sending a local oscillator with the quantum channel. This makes our setup robust and easy to implement. A shared key was established for losses up to 64%.

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Stefan Lorenz, Natalia Korolkova, Gerd Leuchs. 2004-03-08. Continuous variable quantum key distribution using polarization encoding and post selection. https://arxiv.org/abs/quant-ph/0403064

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