A principle which enables the generation of macroscopic Fock and sub-Poissonian states is disclosed. Generic components of the system include: an electromagnetic structure (possessing one or more electromagnetic resonances), a nonlinear electromagnetic element (such as a nonlinear crystal near or inside the structure), and a source of light. In one embodiment, stimulated gain is used to create large numbers of photons in a cavity, but with very low photon number noise (uncertainty) in the cavity, and thus acts as a Fock laser. This Fock laser is capable of producing these states due to a very sharp intensity-dependent gain (or loss) that selects a particular photon number. The disclosed system and method are robust against both atomic and optical decoherence. Various examples of the new Fock laser design are also described.