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%.
@article{arxiv.quant-ph/0403064,
title = {Continuous variable quantum key distribution using polarization encoding and post selection},
author = {Stefan Lorenz and Natalia Korolkova and Gerd Leuchs},
journal= {arXiv preprint arXiv:quant-ph/0403064},
year = {2007}
}