Limitation of decoy-state Scarani-Acin-Ribordy-Gisin quantum-key-distribution protocols with a heralded single-photon source
ShengLi Zhang, Xu‐Bo Zou, Ke Li, Chenhui Jin, Guang‐Can Guo · Physical Review A · 2007
For the Bennett-Brassard 1984 (BB84) quantum key distribution, longer distance and higher key generating rate is shown with a heralded single-photon source (HSPS) [Phys. Rev. A. 73, 032331 (2006)]. In this paper, the performance of the Scarani-Acin-Ribordy-Gisim (SARG) protocol utilizing the HSPS sources is considered and the numerical simulation turns out that still a significant improvement in secret key generating rate can also be observed. It is shown that the security distance for $\mathrm{HSPS}+\mathrm{SARG}$ is $120\phantom{\rule{0.3em}{0ex}}\mathrm{km}$. However, compared with the $\mathrm{HSPS}+\mathrm{BB}84$ protocols, the $\mathrm{HSPS}+\mathrm{SARG}$ protocol has a lower secret key rate and a shorter distance. Thus we show the $\mathrm{HSPS}+\mathrm{BB}84$ implementation is a preferable protocol for long distance transmittance.