Methods and Apparatuses to Generate Fock and Sub-Poissonian States through Nonlinear Optics

A fundamental new effect in nonlinear photonic systems is disclosed herein, called n-photon bound states in the continuum, which can be applied to deterministically create large Fock states, as well as very highly intensity-squeezed states of light. The effect is one in which destructive interference gives a certain quantum state of light an infinite lifetime, despite coexisting in frequency with a radiative continuum. For Kerr nonlinear systems, that state is an n-photon (Fock) state of a particular and tunable n. Experimentally-realizable examples are shown which are capable of producing n-photon Fock states, and states with very large intensity squeezing, such as greater than 10 dB. The effect requires only Kerr nonlinearity and linear frequency-dependent (non-Markovian) dissipation, and is, in principle, applicable at any frequency. The theory and concepts are also immediately applicable to nonlinear bosons besides photons, and thus may be implemented in many other disciplines.