Fig. 1: Experimental results demonstrating the UKF’s performance with respect to excess noise and asymptotic secret key rate compared to other methods.
From: Machine learning aided carrier recovery in continuous-variable quantum key distribution
a Excess noise mean photon number e obtained using three phase compensation methods and b respective estimated secret key rates. The thermal state at the transmitter’s output had a mean photon number N = 2.73, the detector’s electronic noise mean photon number t ≈ 0.022 was trusted and subtracted from e. We used the average value of e and assumed an error reconciliation efficiency β = 0.95 in the key rate calculations. The detector’s optical efficiency of 0.84 was treated as trusted loss, i.e., not accessible to the eavesdropper. Error bars were calculated over 1000 frames for one standard deviation. c Excess noise mean photon number for both phase compensation methods for N = 3.41 and d respective estimated secret key rates, when we used a 10-kHz laser in lieu of the 100-Hz laser in the transmitter. The error bars represent one standard deviation.
