Ghost imaging using two SPAD array detectors: a parameter study towards the realization of a 3D quantum microscope

Quantum ghost imaging can be an important tool in making optical measurements. One of the most useful aspects of ghost imaging is the unique ability to correlate two sets of independently collected information. We aim to use the principles of ghost imaging to build out a 3-dimensional microscope which utilizes detection from two imaging detectors that simultaneously capture entangled light. Further advancements and application of this relatively new imaging method depends on understanding the limits of the optical system. What quality should we expect? Can we image out-of-focus objects? How long do we need to expose? For ghost imaging, these answers are not so obvious. This is because entangled light sources are atypical: the light profile, frequency distribution, and intensity, for instance, all depend on an assortment of parameters associated with how the entangled light was generated. While we cannot practically explore the extent of this configuration space, we present here an exploration of a very accessible range. We show in which ways a commonly used bulk non-linear crystal can alter the imaging capabilities. In this study, we utilize a pair of state-of-the-art, single-photon avalanche diode (SPAD) array detectors. Thus, we also use this study as an opportunity to demonstrate the capabilities of these detectors in their use for ghost imaging applications.