Fig. 2: The measured QBER in each basis, and the count rate in Z basis.
From: Free-running long-distance reference-frame-independent quantum key distribution
Each point is measured within 5 s. a, b shows the QBER of signal (decoy) state on X, Y basis for the total 50.7 h, c shows the QBER of signal state and decoy state on Z basis: \({E}_{\mu }^{ZZ}\) and \({E}_{\nu }^{ZZ}\), and d shows the count rate of signal and decoy state on Z basis: \({N}_{\mu }^{ZZ}\) and \({N}_{\nu }^{ZZ}\).
