We introduce a novel form of decoy-state technique to make the single-photon Bennett 1992 protocol robust against losses and noise of a communication channel. Two uninformative states are prepared by the transmitter in order to prevent the unambiguous state discrimination attack and improve the phase-error rate estimation. The presented method does not require strong reference pulses, additional electronics or extra detectors for its implementation.
@article{arxiv.0907.0493,
title = {Robust Unconditionally Secure Quantum Key Distribution with Two Nonorthogonal and Uninformative States},
author = {Marco Lucamarini and Giovanni Di Giuseppe and Kiyoshi Tamaki},
journal= {arXiv preprint arXiv:0907.0493},
year = {2009}
}