TRANSIENT REGIMES OF ANISOTROPIC LIGHT-BEAM SELF-FOCUSING IN NONLINEAR DISPERSIVE MEDIA

We couple a variational method with an asymptotic analysis to investig ate the transient regimes of optical self-focusing for both positive-d efinite dispersion and mixed dispersion. Initially anisotropic waves a re shown to propagate with two characteristic sizes, which distinctly oscillate along the propagation axis before relaxing to a single one.