Antiphase chaos and intensity dependent dissipations

The dynamics of a laser with an intracavity second harmonic crystal is anal yzed in a model with two modes of one polarization and a third mode orthogo nally polarized. In regimes of global mode coupling, antiphase chaos affect s all modes while the intensity maxima of the third mode appear locked on a period-one dynamics. We explain this curious feature in terms of periodic decoupling of the modes with orthogonal polarizations and intensity depende nt dissipations which force the trajectories onto extremely narrow manifold s. The effect of intensity dependent dissipations on Lyapunov numbers calcu lated in specific parts of the chaotic attractor is also described. [S1063- 651X(99)09402-7].