Figure 3: Background-subtracted auto-correlation functions in position and momentum.
From: Imaging high-dimensional spatial entanglement with a camera
Auto-correlation functions for high and low heralding efficiency configurations for (a) the image plane and (b) the far-field of the crystal, summed over 100,000 images and with the measured background correlation removed. In c and d, we show the same measurements performed with a lower heralding efficiency. Variances along the x′ direction of the high heralding efficiency configuration are indicated. Because of increased coincidence counts attributed to smearing, the correlation function for 
were set to 0 in (a) and (c) for clarity.
