Figure 5
From: Direct Generation and Detection of Quantum Correlated Photons with 3.2 um Wavelength Spacing
(a) Histogram of the raw coincidence counts obtained with (red) and without (blue) input of 3950 nm idler photons. Contribution from the upconversion noise photons and detector dark counts are not subtracted. (b) Measured coincidence (red square), accidental coincidence (green dot), true coincidence (blue dot), plotted as a function of pump peak power. (Inset) accidental-coincidence(green dot) plotted on a smaller scale with quadratic fitting (green solid line). (c) True coincidence-to-accidental coincidence ratio versus pump peak power. Each data point is acquired over an integration time of 300 seconds. The error bars are calculated assuming Poissonian photon counting statistics.
