This is a proposal for research on coherence and fluctuations in quantum optics. The proposal calls for observations of nonclassical features in the second order intensity correlation function of the light produced by interfering the output of an optical parametric oscillator with a coherent local oscillator and, secondly, to characterize the photon counting statistics of an optical parametric oscillator as it is taken from below threshold, through threshold, to above threshold. These investigations are a stepping stone to studies of novel phenomena in atomic spectroscopy, nonlinear optics and precision measurements using light from these sources.
