Quantum correlations from dynamically modulated optical nonlinear interactions

We investigate optical nonlinear interactions in a dynamic environment by studying the generation of photons in spontaneous parametric down conversion inside a nonlinear cavity where the optical path length is periodically modulated in time. We show that the temporal dynamics of the cavity modify the nonlinear interaction and the generated continuous-variable time-frequency entangled biphoton state evolves into a tunable discrete higher-dimensional state in the nonadiabatic modulation regime where the modulation timescales are much faster than the photon lifetime. In this regime, the system mimics effects of a quantum random walk in a photonic lattice with many associated effects, including localized and delocalized wave functions of the generated photons. We also propose generation of time-frequency hyperentangled states in the adiabatic limit. Our analysis shows that the proposed system is promising for applications in quantum simulation and information processing in the time-frequency domain.