Amplitude squeezing from singly resonant frequency-doubling laser

We analyze amplitude squeezing from a singly resonant frequency-doubling laser oscillating at a single frequency. In this laser system, the cavity loss depends on the intensity of the oscillating fundamental field, so that conventional analyses based on a mean-field approximation become invalid in a highly pumped regime. To avoid this inconvenience, we consider spatial evolution of fields both in a laser medium and in a nonlinear crystal. It is predicted for the first time that a combination of excess nonlinearity and modest laser saturation can increase the output noise. We propose novel indices to evaluate the possible noise enhancement and suggest a design rule for squeezed light generation.