Modulational instability of nonlinearly interacting incoherent sea states
P. K. Shukla, M. Marklund+, L. Stenflo+
Institut für Theoretische Physik IV and Centre for Plasma Science and Astrophysics,
Ruhr-Universität Bochum, D-44780 Bochum, Germany
+Centre for Nonlinear Physics, Department of Physics,
Umeå University, SE-901 87 Umeå, Sweden
PACS: 02.60.Cb, 47.15.Hg, 47.35.-i, 92.10.Hm
Abstract
The modulational instability of nonlinearly interacting spatially
incoherent Stokes waves is analyzed. Starting from a pair of nonlinear
Schrödinger equations, we derive a coupled set of wave-kinetic equations by
using the Wigner transform technique. It is shown that the partial coherence
of the interacting waves induces novel effects on the dynamics of crossing
sea states.