MODULATIONAL INSTABILITY OF NONLINEAR-WAVES IN THE RANGE OF ZERO DISPERSION

The effect of high-order dispersion on the modulational instability of nonlinear waves has been investigated. The basic model is the nonline ar Schrodinger equation supplemented with additional terms with third and fourth derivatives. The modulationally unstable waves evolve to th e soliton-type or turbulent state, depending on the stability conditio ns for solitons. The soliton-type state is characterized by periodic g eneration of moving or stationary solitons, the turbulent state by an accumulation of the wave energy in narrow resonance spectral bands. (C ) 1998 Published by Elsevier Science B.V.