Figure 13

(a): The TCSPC histogram of all 1.6 seconds of data once clocks are synchronized (blue, solid), and a Gaussian fit (orange, dashed) of the data confirming the peak is approximately Gaussian (assumed by the processing algorithms). (b): Extinction matrix showing the states received compared to the states transmitted. The situations where the bases do not match, coloured grey, are discarded by the algorithm and do not contribute to the key or the error rate. The bars representing the unmatched bases should all have equal height (0.5 in this normalized figure), we suspect the slight deviation here represents a small misalignment in the angle between the H/V and D/A bases