A quantum imager for intensity correlated photons

We report on a device capable of imaging second-order spatio-temporal correlations g((2))(x, tau) between photons. The imager is based on a monolithic array of single-photon avalanche diodes (SPADs) implemented in CMOS technology and a simple algorithm to treat multiphoton time-of-arrival distributions from different SPAD pairs. It is capable of 80 ps temporal resolution with fluxes as low as 10 photons s(-1) at room temperature. An important application might be the local imaging of g((2)) as a means of confirming the presence of true Bose-Einstein macroscopic coherence (BEC) of cavity exciton polaritons.