Long-distance continuous-variable quantum key distribution with feasible physical noiseless linear amplifiers
Michele Notarnicola, Stefano Olivares · Physical Review A · 2023
Noiseless linear amplifiers (NLAs) provide a powerful tool to achieve long-distance continuous-variable (CV) quantum key distribution (QKD) in the presence of realistic setups with nonunit reconciliation efficiency. We address a NLA-assisted CV QKD protocol implemented via realistic physical NLAs, namely, quantum scissors and single-photon catalysis, and compare their performance with respect to the ideal NLA ${g}^{\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{n}}$. We investigate also the robustness of two schemes against inefficient conditional detection and discuss the two alternative scenarios in which the gain associated with the NLA is either fixed or optimized.