Photon-number-resolving detector with 10 bits of resolution

A photon-number-resolving detector with single-photon resolution is described and demonstrated. It has 10 bits of resolution, does not require cryogenic cooling, and is sensitive to near ir wavelengths. This performance is achieved by flood illuminating a 32x32 element InxGa1-xAsP Geiger-mode avalanche photodiode array that has an integrated counter and digital readout circuit behind each pixel.