Device-independent quantum key distribution (DIQKD) in its current design requires a violation of Bell's inequality between two honest parties, Alice and Bob, who are connected by a quantum channel. However, in reality, quantum channels are lossy, and this can be exploited for attacks based on the detection loophole. Here, we propose a novel approach to DIQKD that overcomes this limitation. In particular, based on a combination between an entropic uncertainty relation and the Clauser-Horne-Shimony-Holt (CHSH) test, we design a DIQKD protocol where the CHSH test is carried out entirely in Alice's laboratory. Thus the loophole caused by channel losses is avoided.
@article{arxiv.1208.0023,
title = {Device-Independent Quantum Key Distribution with Local Bell Test},
author = {Charles Ci Wen Lim and Christopher Portmann and Marco Tomamichel and Renato Renner and Nicolas Gisin},
journal= {arXiv preprint arXiv:1208.0023},
year = {2013}
}