Interaction of dual-frequency pulses in passively mode-locked lasers

We have found, numerically, that three stable pulses of different shapes can exist in systems described by the complex Ginzburg-Landau equation, such as passively mode-locked lasers with a fast saturable absorber. At the same cavity parameter values, however, only two of them can coexist, which two depending on the particular values of the parameters. The region of existence for each pulse is investigated numerically. The interaction between each pair of pulses is studied numerically. Using the interaction plane technique, we have found stable bound states of composite pulses.