Dynamical restrictions to the squeezing achievable by means of a degenerate optical parametric oscillator (OPO) are considered by quantum-statistical diagram techniques. We determine optimal pumping conditions which maximize the degree of squeezing in the output signal of the OPO. The maximal spectral squeezing in the OPO’s output radiation is found to scale as ${\mathit{N}}_2^{\mathrm{-}2/3}$ where ${\mathit{N}}_2$ is the number of photons in the pump mode.

• Received 19 November 1993

DOI:https://doi.org/10.1103/PhysRevA.50.2627