Quantum Non-Gaussian Multiphoton Light

We propose an experimental method of recognizing quantum non-Gaussian multiphoton states. This is a native quantum property of Fock states, the fundamental quantum states with a constant number of particles. Our method allows experimental development and characterization of higher Fock states of light, reaching even beyond the current technical limits of their generation. We experimentally demonstrate that it is capable of distinguishing realistic quantum non-Gaussian light with the mean number of photons up to 5 despite detection efficiency of 50 %. We also provide evidence that our method can help to distinguish the number of single-photon emitters based only on their collective emission.