Recently, a quantum key distribution (QKD) scheme based on entanglement swapping, called measurement-device-independent QKD (mdiQKD), was proposed to bypass all detector side-channel attacks. While mdiQKD is conceptually elegant and offers a supreme level of security, the experimental complexity is challenging for practical systems. For instance, it requires interference between two widely separated independent single-photon sources, and the rates are dependent on detecting two photons - one from each source. Here we experimentally demonstrate a QKD scheme that removes the need for a two-photon system and instead uses the idea of a two-qubit single-photon (TQSP) to significantly simplify the implementation and improve the efficiency of mdiQKD in several aspects.
@article{arxiv.1410.1850,
title = {Detector-Device-Independent Quantum Key Distribution},
author = {Charles Ci Wen Lim and Boris Korzh and Anthony Martin and Felix Bussieres and Rob Thew and Hugo Zbinden},
journal= {arXiv preprint arXiv:1410.1850},
year = {2014}
}