Information in correlation detection for plenoptic imaging purposes

In the present work, we quantify the information content of intensity correlation measurements as compared to conventional intensity detection. In particular, we focus on the problem of estimating the separation between two point-like emitters and evaluate Fisher information for the two types of measurements. We consider two different scenarios: intensity correlations are measured, in the first case, in the image plane, and, in the second case, between the image and the Fourier plane of the object. Both detection schemes are shown to benefit from measuring correlations between the detected intensities, a result that indicates the advantages offered by both quantum and quantum-inspired (i.e., correlation-based) imaging protocols over conventional, intensity based, approaches.