Fig. 2: Source comparison for three main QKD schemes.
From: Enhancing quantum cryptography with quantum dot single-photon sources
Simulated secret key rates using one-way classical post-processing82,83 for (a) BB84 without decoy states, (b) BB84 with infinite decoy states, (c) twin-field with infinite decoy states. The continuum in each plot shows the attainable key rates for QDS ranging from 1 to 100% collection efficiencies, with intermediate curves showing steps of 10%. The dashed line indicates the optimal performance of randomized-phase (RP) PDS. For QDS, pulse lengths were chosen to simultaneously maximize the brightness and single-photon purities from Fig. 1: 3 ps for RE, 8 ps for LA, 12 ps for TPE. Chosen pulse areas: \({\pi }_{{{{\rm{RE}}}}}\) for RE, \(10{\pi }_{{{{\rm{RE}}}}}\) for LA, πTPE for TPE. photon-number populations {pn} up to n = 3 were inferred from the subsequent values of brightness and single-photon purity. Parameters for all plots are: e = 2% single photon error rate, 0.21 dB/km single mode telecom fiber losses, Y0 = 10−9 dark count probability, unit detection efficiency, and error-correcting code inefficiency f = 1.2.
