Sub-Rayleigh imaging enhanced by phase-locked inversion interferometry

Super localization by image inversion interferometry (SLIVER) has recently been implemented to measure the separation of two incoherent point-like sources with promising results. The very few experimental SLIVER demonstrations suffer from the instability of the interferometer adopted. Here we set up an inversion interferometer and eliminate the instability by employing a smart locking scheme. Then we employ the developed system to perform measurement of transverse separation and intensity ratio of two simulated incoherent point-like sources. The implementation of the inversion interferometer locking, on the one hand, improves performance, and on the other hand, makes the system stable, paving the way for real observation campaigns. Using information theory, we insert the work in a rigorous framework to calculate the resolution improvement of our setup when compared with direct imaging.