Figure 2
From: Secret key rate bounds for quantum key distribution with faulty active phase randomization
Secret key rate in logarithmic scale versus the overall system loss for the ideal discrete phase-randomization scenario given by Eq. (1), as a function of the total number of random phases N selected by Alice, when Alice and Bob employ the parameter estimation procedure based on SDP and basis mismatched events considered in this work. Remarkably, as shown in the figure, only eight random phases are enough to deliver a secret key rate already quite close to the ideal scenario of perfect PR-WCPs, where the phase of each pulse is uniformly random in \([0,2\pi )\)