To increase dramatically the distance and the secure key generation rate of quantum key distribution (QKD), the idea of quantum decoys--signals of different intensities--has recently been proposed. Here, we present the first experimental implementation of decoy state QKD. By making simple modifications to a commercial quantum key distribution system, we show that a secure key generation rate of 165bit/s, which is 1/4 of the theoretical limit, can be obtained over 15km of a Telecom fiber. We also show that with the same experimental parameters, not even a single bit of secure key can be extracted with a non-decoy-state protocol. Compared to building single photon sources, decoy state QKD is a much simpler method for increasing the distance and key generation rate of unconditionally secure QKD.
@article{arxiv.quant-ph/0503192,
title = {Experimental Quantum Key Distribution with Decoy States},
author = {Yi Zhao and Bing Qi and Xiongfeng Ma and Hoi-Kwong Lo and Li Qian},
journal= {arXiv preprint arXiv:quant-ph/0503192},
year = {2009}
}
Comments
Revised Version, 4 pages, one figures, two-column format