Fluctuations in transient nonlinear interactions of opposed waves

The three-frequency interaction of opposed waves in a medium with anomalous dispersion is considered and a calculation is given of the ranges of the parameters (absorption and length of the nonlinear medium) in which parametric oscillations can be excited. The conditions are found under which fluctuations appear during the establishment of the steady-state amplitudes. It is found that the period of fluctuations during the transient stage is a nonmonotonic function of the length of the nonlinear medium.