Figure 10

Noise reduction factor for the single-mode thermal state as a function of the mean number of photons detected at a BS output. Colored dots and error bars: experimental data obtained with the CAEN system PSAU (\(g = 12\mbox{ dB}\)) and DT5720 digitizer integrating the traces over \(\tau =48\mbox{ ns}\) (black dots) and \(\tau =80\mbox{ ns}\) (red dots); colored lines: theoretical expectations according to Eq. (5). The fitting parameters for \(\tau =48\mbox{ ns}\) are: \(\epsilon = 0.029\), \(\langle m_{\text{1dc}}\rangle = 0.231\), \(\langle m_{\text{2dc}}\rangle = 0.569\), \(t=0.999\) and \(\chi ^{(2)}=4.8\), while those for \(\tau = 80\mbox{ ns}\) are: \(\epsilon = 0.031\), \(\langle m_{\text{1dc}}\rangle = 0.205\), \(\langle m_{\text{2dc}}\rangle = 0.595\), \(t=0.999\) and \(\chi ^{(2)}=3.6\)